Refactor (in support of testing) (#2)

Reviewed-on: #2
Co-authored-by: Jack Jackson <scubbojj@gmail.com>
Co-committed-by: Jack Jackson <scubbojj@gmail.com>

TODO.txt

@@ -10,4 +10,10 @@
 - [ ] Blog about this ;)
 - [ ] Tests!
   - [ ] ...
-  - [ ] Profit?
+  - [ ] Profit?
+- [ ] Migrate into Gitea's own [Issue Tracker](https://gitea.scubbo.org/scubbo/commit-report-sync/issues)
+- [ ] Use a more fully-featured logging system than `console.log` (at least with different logging levels!)
+
+# Done
+
+- [X]  Remove `parentHashes`, never ended up being needed

dist/index.js

@@ -25641,6 +25641,156 @@ module.exports = {
 }
 
 
+/***/ }),
+
+/***/ 1243:
+/***/ ((__unused_webpack_module, exports, __nccwpck_require__) => {
+
+"use strict";
+
+// Abstract-away Git interactions, so they can be mocked in tests
+Object.defineProperty(exports, "__esModule", ({ value: true }));
+exports.gitClone = gitClone;
+exports.getNLatestCommits = getNLatestCommits;
+exports.getCommitsSinceLatestBeforeGivenDate = getCommitsSinceLatestBeforeGivenDate;
+exports.insertRepresentativeCommit = insertRepresentativeCommit;
+exports.gitPush = gitPush;
+const child_process_1 = __nccwpck_require__(5317);
+const fs_1 = __nccwpck_require__(9896);
+const date_fns_1 = __nccwpck_require__(4367);
+function gitClone(dir, url) {
+    (0, child_process_1.execSync)(`git clone ${url} ${dir}`, { cwd: dir });
+}
+function getNLatestCommits(dir, n) {
+    const logOutput = (0, child_process_1.execSync)(
+    // If you want to copy this formatting for debugging, it's:
+    //
+    // --pretty=format:'{"hash":"%h","author_name":"%an","author_email":"%ae","date":"%ai","message":"%s"}'
+    //
+    // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
+    // of string-parsing to consider here, I wouldn't want to bet without testing!
+    //eslint-disable-next-line no-useless-escape
+    `git log --max-count=${n} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`, { cwd: dir });
+    const logLines = logOutput.toString().split('\n');
+    return logLines.map(commitLine => {
+        // https://gist.github.com/textarcana/1306223
+        const parsed = JSON.parse(commitLine);
+        return {
+            hash: parsed.hash,
+            author_name: parsed.author_name,
+            author_email: parsed.author_email,
+            repo_path: dir,
+            date: parsed.date,
+            message: parsed.message
+        };
+    });
+}
+function getCommitsSinceLatestBeforeGivenDate(dir, date) {
+    try {
+        const countingLogOutput = (0, child_process_1.execSync)(`git log --since=${date.toISOString()} --pretty=oneline`, { cwd: dir });
+        const countedNumber = countingLogOutput.toString().split('\n').length;
+        console.log(`DEBUG - countedNumber (how many commits in target repo since oldest source commit) is: ${countedNumber}`);
+        // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
+        // of string-parsing to consider here, I wouldn't want to bet without testing!
+        const logOutput = (0, child_process_1.execSync)(
+        //eslint-disable-next-line no-useless-escape
+        `git log --max-count=${countedNumber + 1} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`, { cwd: dir });
+        const logLines = logOutput.toString().split('\n');
+        return logLines.map(commitLine => {
+            const parsed = JSON.parse(commitLine);
+            return {
+                hash: parsed.hash,
+                author_name: parsed.author_name,
+                author_email: parsed.author_email,
+                repo_path: dir,
+                date: parsed.date,
+                message: parsed.message
+            };
+        });
+    }
+    catch (e) {
+        const error = e;
+        // No commits in the target repo - return an empty array, which will result in the first representative commit
+        // being made as the first commit. And then we can iterate as normal (recalling that the target history is
+        // refreshed _from local repo_ - incurring no network charges) from there on.
+        const errorOutputAsString = '' + error.output[2];
+        if (!errorOutputAsString.includes('does not have any commits yet')) {
+            console.log(`Unexpected error: ${errorOutputAsString}`);
+            throw Error(`Unexpected error while building target commit history`, {
+                cause: error
+            });
+        }
+        // Fresh target repo - just write into it (by returning an empty array of target commits as target history)
+        // (i.e. doing nothing)
+        return [];
+    }
+}
+function insertRepresentativeCommit(dir, sourceRepo, sourceCommit, targetCommit, followOnTargetCommit) {
+    // If there is a target commit,
+    if (targetCommit != undefined) {
+        (0, child_process_1.execSync)(`git reset --hard ${targetCommit.hash}`, {
+            cwd: dir
+        });
+    }
+    createRepresentativeCommit(dir, sourceRepo, sourceCommit);
+    // Then, if there is a follow-on target commit, we need to cherry-pick it onto the source commit:
+    if (followOnTargetCommit != undefined) {
+        (0, child_process_1.execSync)(`git cherry-pick ${followOnTargetCommit.hash}`, {
+            cwd: dir
+        });
+    } // else - nothing to cherry-pick back on top 
+}
+function gitPush(dir, tokenForTargetRepo, targetRepoId) {
+    // Note that it must be a `-f`, because we are literally rewriting history.
+    (0, child_process_1.execSync)(`git push -f https://unused-username:${tokenForTargetRepo}@${targetRepoId.domain}/${targetRepoId.owner}/${targetRepoId.name}`, {
+        cwd: dir
+    });
+    // TODO - it'd be nice - before this `git push` is probably best - to add a `README.md` comment acknowledging
+    // the sync
+}
+function createRepresentativeCommit(dir, sourceRepo, sourceCommit) {
+    // Create a commit that represents the source commit, but with a filename that is generated from the source commit's
+    // metadata.
+    //
+    // This is guaranteed to not cause conflicts with other commits, because the filename is generated from the source
+    // commit's metadata, and no two source commits will have the same metadata.
+    // (OK sure _technically_ these could have a collision, but...like...what are the odds?)
+    // TODO - figure out what the odds actually are, that'd be fun :P
+    const filename = `${sourceRepo.owner}/${sourceRepo.name}/${sourceCommit.hash}`;
+    (0, fs_1.mkdirSync)(dir + '/' + sourceRepo.owner + '/' + sourceRepo.name, { recursive: true });
+    (0, child_process_1.execSync)(`touch ${filename}`, {
+        cwd: dir
+    });
+    (0, child_process_1.execSync)(`git add ${filename}`, {
+        cwd: dir
+    });
+    // Seems like setting `--author` on `git commit` is not sufficient - still need to set `user` as well (I guess those
+    // are the difference between `comitted by` and `written by`?)
+    // Confirmed by following the instructions [here](https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-github-profile/managing-contribution-settings-on-your-profile/why-are-my-contributions-not-showing-up-on-my-profile#your-local-git-commit-email-isnt-connected-to-your-account)
+    // to check the "made by" address, and confirming that it did not match the email set in the `--author` flag.
+    // Note that, contrary to advice given by the CLI, this does not use the global config, but the local one - because,
+    // otherwise, if this was run locally, it would mess up the host system's config.
+    (0, child_process_1.execSync)(`git config user.email "${sourceCommit.author_email}"`, { cwd: dir });
+    (0, child_process_1.execSync)(`git config user.name "${sourceCommit.author_name}"`, { cwd: dir });
+    try {
+        // Do _not_ arbitrarily remove the `hash` - it's used for signalling identity in `main()`
+        const args = `"${sourceRepo.owner}/${sourceRepo.name}: ${sourceCommit.message} - ${sourceCommit.hash}" --date="${(0, date_fns_1.format)(sourceCommit.date, 'yyyy-MM-dd HH:mm:ss')}" --author="${sourceCommit.author_name} <${sourceCommit.author_email}>"`;
+        console.log(`About to commit with args ${args}`);
+        // https://github.com/Shpota/github-activity-generator/blob/main/contribute.py#L63
+        // "%Y-%m-%d %H:%M:%S"
+        (0, child_process_1.execSync)(`git commit -m ${args}`, {
+            cwd: dir
+        });
+    }
+    catch (e) {
+        console.log(e);
+        const error = e;
+        console.log(`DEBUG - error while creating representative commit: ${'' + error.output[2]} ... ${'' + error.output[1]}`);
+        throw e;
+    }
+}
+
+
 /***/ }),
 
 /***/ 9407:
@@ -25729,38 +25879,14 @@ run();
 
 Object.defineProperty(exports, "__esModule", ({ value: true }));
 exports.main = main;
-exports.buildSourceCommitHistory = buildSourceCommitHistory;
-exports.buildTargetCommitHistory = buildTargetCommitHistory;
 const types_1 = __nccwpck_require__(8522);
-const child_process_1 = __nccwpck_require__(5317);
 const fs_1 = __nccwpck_require__(9896);
-const date_fns_1 = __nccwpck_require__(4367);
+const git_1 = __nccwpck_require__(1243);
 const WORKING_DIR = './working';
 const SOURCE_DIR = WORKING_DIR + '/source';
 const TARGET_DIR = WORKING_DIR + '/target';
-async function main(sourceRepo, targetRepo, dryRun, tokenForTargetRepo) {
+async function main(sourceRepoId, targetRepoId, dryRun, tokenForTargetRepo) {
-    // It _shouldn't_ ever exist, but it if did, something weird is going on.
+    setPreconditions(tokenForTargetRepo, sourceRepoId, targetRepoId);
-    if ((0, fs_1.existsSync)(WORKING_DIR) || (0, fs_1.existsSync)(SOURCE_DIR) || (0, fs_1.existsSync)(TARGET_DIR)) {
-        throw new Error('Working directory already exists/populated');
-    }
-    if (tokenForTargetRepo == '') {
-        throw new Error('token_for_target_repo is required');
-    }
-    (0, fs_1.mkdirSync)(WORKING_DIR);
-    (0, fs_1.mkdirSync)(SOURCE_DIR);
-    (0, fs_1.mkdirSync)(TARGET_DIR);
-    console.log(`DEBUG - sourceRepoPath: ${(0, types_1.repoString)(sourceRepo)}`);
-    console.log(`DEBUG - targetRepoPath: ${(0, types_1.repoString)(targetRepo)}`);
-    // TODO - allow parameterizing how far back in history to checkout (because it might take a long time for older
-    // repos and, once synced initially, it won't have to go back further than a single one in most cases)
-    const sourceRepoCloneCommand = `git clone https://${(0, types_1.repoString)(sourceRepo)} ${SOURCE_DIR}`;
-    console.log(`DEBUG - sourceRepoCloneCommand: ${sourceRepoCloneCommand}`);
-    (0, child_process_1.execSync)(sourceRepoCloneCommand);
-    (0, child_process_1.execSync)(`git clone https://${(0, types_1.repoString)(targetRepo)} ${TARGET_DIR}`);
-    // Seems like setting `--author` on `git commit` is not sufficient - still need to set `user` as well (I guess those
-    // are the difference between `comitted by` and `written by`?)
-    (0, child_process_1.execSync)(`git config --global user.email "commit-report-sync-bot@scubbo.org"`, { cwd: TARGET_DIR });
-    (0, child_process_1.execSync)(`git config --global user.name "Commit Report Sync Bot"`, { cwd: TARGET_DIR });
     // Logic:
     // * Go back as far in source commit history as the given number of commits
     // * For each commit, check if it is recorded in the target repo
@@ -25781,7 +25907,7 @@ async function main(sourceRepo, targetRepo, dryRun, tokenForTargetRepo) {
     // only been alive so many years - there's a hard limit on the rate of code I could possibly have generated, which
     // is small compared to, y'know, _companies_. And I don't see organizations of that size caring about GitHub
     // contribution history at whole-org scale - and if they do, it'd be proportionally simple for them to implement it.
-    const sourceCommitHistory = buildSourceCommitHistory(SOURCE_DIR, 10);
+    const sourceCommitHistory = (0, git_1.getNLatestCommits)(SOURCE_DIR, 10);
     // Calling `doSomethingTo(sourceCommitHistory.reverse()); doSomethingElseTo(sourceCommitHistory.reverse());` results
     // in the second invocation receiving the double-reversed array.
     const reversedSourceCommitHistory = sourceCommitHistory.reverse();
@@ -25793,11 +25919,12 @@ async function main(sourceRepo, targetRepo, dryRun, tokenForTargetRepo) {
     // than abandoning the target tree after the insertion point and trusting in later operation to rebuild it - because
     // the target repo's tree will have representations of commits from _other_ (source)repos too, which we cannot
     // recreate without their context)
-    let targetCommitHistory = buildTargetCommitHistory(TARGET_DIR, reversedSourceCommitHistory[0].date);
+    let targetCommitHistory = (0, git_1.getCommitsSinceLatestBeforeGivenDate)(TARGET_DIR, reversedSourceCommitHistory[0].date);
     for (const sourceCommit of reversedSourceCommitHistory) {
         // "(Index of) First Target Commit that is earlier than (or equal to) the source commit"
         const targetCommitIndex = targetCommitHistory.findIndex(c => c.date <= sourceCommit.date);
         console.log(`DEBUG - targetCommitIndex: ${targetCommitIndex}. targetCommitHistory: ${JSON.stringify(targetCommitHistory)}`);
+        // TODO - refactor this to use guard clauses more than nested-ifs
         if (targetCommitIndex != -1) {
             const targetCommit = targetCommitHistory[targetCommitIndex];
             // If the target commit is a representation of the source commit, we can skip it
@@ -25819,7 +25946,7 @@ async function main(sourceRepo, targetRepo, dryRun, tokenForTargetRepo) {
                     else {
                         followOnTargetCommit = targetCommitHistory[targetCommitIndex - 1];
                     }
-                    insertRepresentativeCommit(sourceRepo, sourceCommit, targetCommit, followOnTargetCommit);
+                    (0, git_1.insertRepresentativeCommit)(TARGET_DIR, sourceRepoId, sourceCommit, targetCommit, followOnTargetCommit);
                     // And then regenerate the target commit history
                     // Thankfully, we only need to do this back to immediately preceding the _just processed_ source
                     // commit (since we know that all the rest of the source commits to be processed will be after it),
@@ -25828,147 +25955,42 @@ async function main(sourceRepo, targetRepo, dryRun, tokenForTargetRepo) {
                     // compared), albeit approximately-halved - but I'm gambling on the fact that that should still take
                     // negligible practical time at usual repo sizes - at least, the ones I'm 
                     // this quadratic portion should be negligible, though - and, even if it isn't, it definitely will
-                    targetCommitHistory = buildTargetCommitHistory(TARGET_DIR, sourceCommit.date);
+                    targetCommitHistory = (0, git_1.getCommitsSinceLatestBeforeGivenDate)(TARGET_DIR, sourceCommit.date);
                 }
             }
             console.log(`DEBUG - targetCommit: ${targetCommit.hash}`);
         }
         else {
             console.log(`DEBUG - could not find a targetCommit that is earlier than or equal to the sourceCommit ${sourceCommit.hash} - therefore, writing the source commit's representation onto the current HEAD of target repo`);
-            insertRepresentativeCommit(sourceRepo, sourceCommit, undefined, undefined);
+            (0, git_1.insertRepresentativeCommit)(TARGET_DIR, sourceRepoId, sourceCommit, undefined, undefined);
             // As above, have to regenerate history after mutation
-            targetCommitHistory = buildTargetCommitHistory(TARGET_DIR, sourceCommit.date);
+            targetCommitHistory = (0, git_1.getCommitsSinceLatestBeforeGivenDate)(TARGET_DIR, sourceCommit.date);
         }
     }
     // OK, that's it - we've processed all the source commits, and we've inserted all the necessary target commits.
     // We can just `git push` to the target repo now.
-    //
-    // Note that it must be a `-f`, because we are literally rewriting history.
     if (!dryRun) {
-        (0, child_process_1.execSync)(`git push -f https://unused-username:${tokenForTargetRepo}@${targetRepo.domain}/${targetRepo.owner}/${targetRepo.name}`, {
+        (0, git_1.gitPush)(TARGET_DIR, tokenForTargetRepo, targetRepoId);
-            cwd: TARGET_DIR
-        });
-        // TODO - it'd be nice - before this `git push` is probably best - to add a `README.md` comment acknowledging
-        // the sync
     }
     return;
 }
-function buildSourceCommitHistory(path, numCommits) {
+function setPreconditions(tokenForTargetRepo, sourceRepoId, targetRepoId) {
-    console.log(`DEBUG - building source commit history for ${path} with max count ${numCommits}`);
+    // It _shouldn't_ ever exist, but it if did, something weird is going on.
-    const output = [];
+    if ((0, fs_1.existsSync)(WORKING_DIR) || (0, fs_1.existsSync)(SOURCE_DIR) || (0, fs_1.existsSync)(TARGET_DIR)) {
-    const logOutput = (0, child_process_1.execSync)(
+        throw new Error('Working directory already exists/populated');
-    // If you want to copy this formatting for debugging, it's:
-    //
-    // --pretty=format:'{"hash":"%h","author_name":"%an","author_email":"%ae","date":"%ai","message":"%s"}'
-    //
-    // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
-    // of string-parsing to consider here, I wouldn't want to bet without testing!
-    //eslint-disable-next-line no-useless-escape
-    `git log --max-count=${numCommits} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`, { cwd: path });
-    const logLines = logOutput.toString().split('\n');
-    for (const line of logLines) {
-        const commit = parseCommit(path, line);
-        output.push(commit);
     }
-    return output;
+    if (tokenForTargetRepo == '') {
-}
+        throw new Error('token_for_target_repo is required');
-function buildTargetCommitHistory(path, oldestDateInSourceCommitHistory) {
-    console.log(`DEBUG - building target commit history for ${path} with oldest date ${oldestDateInSourceCommitHistory.toISOString()}`);
-    const output = [];
-    try {
-        const countingLogOutput = (0, child_process_1.execSync)(`git log --since=${oldestDateInSourceCommitHistory.toISOString()} --pretty=oneline`, { cwd: path });
-        const countedNumber = countingLogOutput.toString().split('\n').length;
-        console.log(`DEBUG - countedNumber (how many commits in target repo since oldest source commit) is: ${countedNumber}`);
-        // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
-        // of string-parsing to consider here, I wouldn't want to bet without testing!
-        const logOutput = (0, child_process_1.execSync)(
-        //eslint-disable-next-line no-useless-escape
-        `git log --max-count=${countedNumber + 1} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`, { cwd: path });
-        const logLines = logOutput.toString().split('\n');
-        for (const line of logLines) {
-            const commit = parseCommit(path, line);
-            output.push(commit);
-        }
-    }
-    catch (e) {
-        const error = e;
-        // Now you can safely access properties
-        // No commits in the target repo - return an empty array, which will result in the first representative commit 
-        // being made as the first commit. And then we can iterate as normal (recalling that the target history is 
-        // refreshed _from local repo_ - incurring no network charges) from there on.
-        const errorOutputAsString = '' + error.output[2];
-        if (!errorOutputAsString.includes('does not have any commits yet')) {
-            console.log(`Unexpected error: ${errorOutputAsString}`);
-            throw Error(`Unexpected error while building target commit history`, {
-                cause: error
-            });
-        }
-        // Fresh target repo - just write into it (by returning an empty array of target commits as target history)
-        // (i.e. doing nothing)
-    }
-    console.log(`As final output of buildTargetCommitHistory, preceding ${oldestDateInSourceCommitHistory.toISOString()}, output is ${JSON.stringify(output)}`);
-    return output;
-}
-// https://gist.github.com/textarcana/1306223
-function parseCommit(repo_path, line) {
-    console.log(`DEBUG - line: ${line}, for path ${repo_path}`);
-    const parsed = JSON.parse(line);
-    return {
-        hash: parsed['hash'],
-        author_name: parsed['author_name'],
-        author_email: parsed['author_email'],
-        repo_path: repo_path,
-        date: new Date(parsed['date']),
-        message: parsed['message'],
-    };
-}
-function insertRepresentativeCommit(sourceRepo, sourceCommit, targetCommit, followOnTargetCommit) {
-    // If there is a target commit,
-    if (targetCommit != undefined) {
-        (0, child_process_1.execSync)(`git reset --hard ${targetCommit.hash}`, {
-            cwd: TARGET_DIR
-        });
-    }
-    createRepresentativeCommit(sourceRepo, sourceCommit);
-    // Then, if there is a follow-on target commit, we need to cherry-pick it onto the source commit:
-    if (followOnTargetCommit != undefined) {
-        (0, child_process_1.execSync)(`git cherry-pick ${followOnTargetCommit.hash}`, {
-            cwd: TARGET_DIR
-        });
-    } // else - nothing to cherry-pick back on top
-}
-function createRepresentativeCommit(sourceRepo, sourceCommit) {
-    // Create a commit that represents the source commit, but with a filename that is generated from the source commit's
-    // metadata.
-    //
-    // This is guaranteed to not cause conflicts with other commits, because the filename is generated from the source
-    // commit's metadata, and no two source commits will have the same metadata.
-    // (OK sure _technically_ these could have a collision, but...like...what are the odds?)
-    // TODO - figure out what the odds actually are, that'd be fun :P
-    const filename = `${sourceRepo.owner}/${sourceRepo.name}/${sourceCommit.hash}`;
-    (0, fs_1.mkdirSync)(TARGET_DIR + '/' + sourceRepo.owner + '/' + sourceRepo.name, { recursive: true });
-    (0, child_process_1.execSync)(`touch ${filename}`, {
-        cwd: TARGET_DIR
-    });
-    (0, child_process_1.execSync)(`git add ${filename}`, {
-        cwd: TARGET_DIR
-    });
-    try {
-        // Do _not_ arbitrarily remove the `hash` - it's used for signalling identity in `main()`
-        const args = `"${sourceRepo.owner}/${sourceRepo.name}: ${sourceCommit.message} - ${sourceCommit.hash}" --date="${(0, date_fns_1.format)(sourceCommit.date, 'yyyy-MM-dd HH:mm:ss')}" --author="${sourceCommit.author_name} <${sourceCommit.author_email}>"`;
-        console.log(`About to commit with args ${args}`);
-        // https://github.com/Shpota/github-activity-generator/blob/main/contribute.py#L63
-        // "%Y-%m-%d %H:%M:%S"
-        (0, child_process_1.execSync)(`git commit -m ${args}`, {
-            cwd: TARGET_DIR
-        });
-    }
-    catch (e) {
-        console.log(e);
-        const error = e;
-        console.log(`DEBUG - error while creating representative commit: ${'' + error.output[2]} ... ${'' + error.output[1]}`);
-        throw e;
     }
+    (0, fs_1.mkdirSync)(WORKING_DIR);
+    (0, fs_1.mkdirSync)(SOURCE_DIR);
+    (0, fs_1.mkdirSync)(TARGET_DIR);
+    console.log(`DEBUG - sourceRepoPath: ${(0, types_1.repoString)(sourceRepoId)}`);
+    console.log(`DEBUG - targetRepoPath: ${(0, types_1.repoString)(targetRepoId)}`);
+    // TODO - allow parameterizing how far back in history to checkout (because it might take a long time for older
+    // repos and, once synced initially, it won't have to go back further than a single one in most cases)
+    (0, git_1.gitClone)(SOURCE_DIR, `https://${(0, types_1.repoString)(sourceRepoId)}`);
+    (0, git_1.gitClone)(TARGET_DIR, `https://${(0, types_1.repoString)(targetRepoId)}`);
 }
 
 

src/git.ts

@@ -0,0 +1,151 @@
+// Abstract-away Git interactions, so they can be mocked in tests
+
+import { execSync } from "child_process";
+import { Commit, ExecSyncError, RepoId } from "./types";
+import { mkdirSync } from "fs";
+import { format } from 'date-fns';
+
+export function gitClone(dir: string, url: string) {
+    execSync(`git clone ${url} ${dir}`, { cwd: dir });
+}
+
+export function getNLatestCommits(dir: string, n: number): Commit[] {
+    const logOutput = execSync(
+        // If you want to copy this formatting for debugging, it's:
+        //
+        // --pretty=format:'{"hash":"%h","author_name":"%an","author_email":"%ae","date":"%ai","message":"%s"}'
+        //
+        // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
+        // of string-parsing to consider here, I wouldn't want to bet without testing!
+        //eslint-disable-next-line no-useless-escape
+        `git log --max-count=${n} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`,
+        { cwd: dir }
+    );
+    const logLines = logOutput.toString().split('\n')
+    return logLines.map(commitLine => {
+        // https://gist.github.com/textarcana/1306223
+        const parsed = JSON.parse(commitLine)
+        return {
+            hash: parsed.hash,
+            author_name: parsed.author_name,
+            author_email: parsed.author_email,
+            repo_path: dir,
+            date: parsed.date,
+            message: parsed.message
+        }
+    });
+}
+
+export function getCommitsSinceLatestBeforeGivenDate(dir: string, date: Date): Commit[] {
+    try {
+        const countingLogOutput = execSync(
+            `git log --since=${date.toISOString()} --pretty=oneline`,
+            { cwd: dir }
+        );
+        const countedNumber = countingLogOutput.toString().split('\n').length;
+        console.log(`DEBUG - countedNumber (how many commits in target repo since oldest source commit) is: ${countedNumber}`);
+        // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
+        // of string-parsing to consider here, I wouldn't want to bet without testing!
+        const logOutput = execSync(
+            //eslint-disable-next-line no-useless-escape
+            `git log --max-count=${countedNumber+1} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`,
+            { cwd: dir }
+        );
+        const logLines = logOutput.toString().split('\n');
+        return logLines.map(commitLine => {
+            const parsed = JSON.parse(commitLine)
+            return {
+                hash: parsed.hash,
+                author_name: parsed.author_name,
+                author_email: parsed.author_email,
+                repo_path: dir,
+                date: parsed.date,
+                message: parsed.message
+            }
+        });
+    } catch (e) {
+        const error = e as ExecSyncError
+        // No commits in the target repo - return an empty array, which will result in the first representative commit
+        // being made as the first commit. And then we can iterate as normal (recalling that the target history is
+        // refreshed _from local repo_ - incurring no network charges) from there on.
+        const errorOutputAsString = '' + error.output[2]
+        if (!errorOutputAsString.includes('does not have any commits yet')) {
+            console.log(`Unexpected error: ${errorOutputAsString}`);
+            throw Error(`Unexpected error while building target commit history`, {
+                cause: error
+            })
+        }
+        // Fresh target repo - just write into it (by returning an empty array of target commits as target history)
+        // (i.e. doing nothing)
+        return [];
+    }
+}
+
+export function insertRepresentativeCommit(dir: string,sourceRepo: RepoId, sourceCommit: Commit, targetCommit: Commit | undefined, followOnTargetCommit: Commit | undefined): void {
+    // If there is a target commit,
+    if (targetCommit != undefined) {
+        execSync(`git reset --hard ${targetCommit.hash}`, {
+            cwd: dir
+        })
+    }
+
+    createRepresentativeCommit(dir,sourceRepo, sourceCommit);
+    // Then, if there is a follow-on target commit, we need to cherry-pick it onto the source commit:
+    if (followOnTargetCommit != undefined) {
+        execSync(`git cherry-pick ${followOnTargetCommit.hash}`, {
+            cwd: dir
+        })
+    }// else - nothing to cherry-pick back on top 
+}
+
+export function gitPush(dir: string, tokenForTargetRepo: string, targetRepoId: RepoId) {
+    // Note that it must be a `-f`, because we are literally rewriting history.
+    execSync(`git push -f https://unused-username:${tokenForTargetRepo}@${targetRepoId.domain}/${targetRepoId.owner}/${targetRepoId.name}`, {
+        cwd: dir
+    })
+    // TODO - it'd be nice - before this `git push` is probably best - to add a `README.md` comment acknowledging
+    // the sync
+}
+
+function createRepresentativeCommit(dir: string, sourceRepo: RepoId,sourceCommit: Commit) {
+    // Create a commit that represents the source commit, but with a filename that is generated from the source commit's
+    // metadata.
+    //
+    // This is guaranteed to not cause conflicts with other commits, because the filename is generated from the source
+    // commit's metadata, and no two source commits will have the same metadata.
+    // (OK sure _technically_ these could have a collision, but...like...what are the odds?)
+    // TODO - figure out what the odds actually are, that'd be fun :P
+    const filename = `${sourceRepo.owner}/${sourceRepo.name}/${sourceCommit.hash}`
+    mkdirSync(dir + '/' + sourceRepo.owner + '/' + sourceRepo.name, { recursive: true });
+    execSync(`touch ${filename}`, {
+        cwd: dir
+    })
+    execSync(`git add ${filename}`, {
+        cwd: dir
+    })
+
+    // Seems like setting `--author` on `git commit` is not sufficient - still need to set `user` as well (I guess those
+    // are the difference between `comitted by` and `written by`?)
+    // Confirmed by following the instructions [here](https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-github-profile/managing-contribution-settings-on-your-profile/why-are-my-contributions-not-showing-up-on-my-profile#your-local-git-commit-email-isnt-connected-to-your-account)
+    // to check the "made by" address, and confirming that it did not match the email set in the `--author` flag.
+    // Note that, contrary to advice given by the CLI, this does not use the global config, but the local one - because,
+    // otherwise, if this was run locally, it would mess up the host system's config.
+    execSync(`git config user.email "${sourceCommit.author_email}"`, { cwd: dir });
+    execSync(`git config user.name "${sourceCommit.author_name}"`, { cwd: dir });
+
+    try {
+        // Do _not_ arbitrarily remove the `hash` - it's used for signalling identity in `main()`
+        const args = `"${sourceRepo.owner}/${sourceRepo.name}: ${sourceCommit.message} - ${sourceCommit.hash}" --date="${format(sourceCommit.date, 'yyyy-MM-dd HH:mm:ss')}" --author="${sourceCommit.author_name} <${sourceCommit.author_email}>"`;
+        console.log(`About to commit with args ${args}`);
+        // https://github.com/Shpota/github-activity-generator/blob/main/contribute.py#L63
+        // "%Y-%m-%d %H:%M:%S"
+        execSync(`git commit -m ${args}`, {
+            cwd: dir
+        })
+    } catch (e) {
+        console.log(e);
+        const error = e as ExecSyncError;
+        console.log(`DEBUG - error while creating representative commit: ${'' + error.output[2]} ... ${'' + error.output[1]}`);
+        throw e;
+    }
+}

src/main.ts

@@ -1,37 +1,13 @@
-import { Repo, repoString, Commit, ExecSyncError } from './types';
+import { RepoId, repoString, Commit } from './types';
-import { execSync } from 'child_process';
 import { existsSync, mkdirSync } from 'fs';
-
+import { getCommitsSinceLatestBeforeGivenDate, getNLatestCommits, gitClone, gitPush, insertRepresentativeCommit } from './git';
-import { format } from 'date-fns';
 
 const WORKING_DIR = './working';
 const SOURCE_DIR = WORKING_DIR + '/source';
 const TARGET_DIR = WORKING_DIR + '/target';
 
-export async function main(sourceRepo: Repo, targetRepo: Repo, dryRun: boolean, tokenForTargetRepo: string) {
+export async function main(sourceRepoId: RepoId, targetRepoId: RepoId, dryRun: boolean, tokenForTargetRepo: string) {
-    // It _shouldn't_ ever exist, but it if did, something weird is going on.
+    setPreconditions(tokenForTargetRepo, sourceRepoId, targetRepoId);
-    if (existsSync(WORKING_DIR) || existsSync(SOURCE_DIR) || existsSync(TARGET_DIR)) {
-        throw new Error('Working directory already exists/populated');
-    }
-
-    if (tokenForTargetRepo == '') {
-        throw new Error('token_for_target_repo is required');
-    }
-
-    mkdirSync(WORKING_DIR);
-    mkdirSync(SOURCE_DIR);
-    mkdirSync(TARGET_DIR);
-
-    console.log(`DEBUG - sourceRepoPath: ${repoString(sourceRepo)}`)
-
-    console.log(`DEBUG - targetRepoPath: ${repoString(targetRepo)}`)
-
-    // TODO - allow parameterizing how far back in history to checkout (because it might take a long time for older
-    // repos and, once synced initially, it won't have to go back further than a single one in most cases)
-    const sourceRepoCloneCommand = `git clone https://${repoString(sourceRepo)} ${SOURCE_DIR}`
-    console.log(`DEBUG - sourceRepoCloneCommand: ${sourceRepoCloneCommand}`);
-    execSync(sourceRepoCloneCommand);
-    execSync(`git clone https://${repoString(targetRepo)} ${TARGET_DIR}`);
 
     // Logic:
     // * Go back as far in source commit history as the given number of commits
@@ -53,7 +29,7 @@ export async function main(sourceRepo: Repo, targetRepo: Repo, dryRun: boolean,
     // only been alive so many years - there's a hard limit on the rate of code I could possibly have generated, which
     // is small compared to, y'know, _companies_. And I don't see organizations of that size caring about GitHub
     // contribution history at whole-org scale - and if they do, it'd be proportionally simple for them to implement it.
-    const sourceCommitHistory = buildSourceCommitHistory(SOURCE_DIR, 10);
+    const sourceCommitHistory = getNLatestCommits(SOURCE_DIR, 10);
     
     // Calling `doSomethingTo(sourceCommitHistory.reverse()); doSomethingElseTo(sourceCommitHistory.reverse());` results
     // in the second invocation receiving the double-reversed array.
@@ -66,12 +42,13 @@ export async function main(sourceRepo: Repo, targetRepo: Repo, dryRun: boolean,
     // than abandoning the target tree after the insertion point and trusting in later operation to rebuild it - because
     // the target repo's tree will have representations of commits from _other_ (source)repos too, which we cannot
     // recreate without their context)
-    let targetCommitHistory = buildTargetCommitHistory(TARGET_DIR, reversedSourceCommitHistory[0].date);
+    let targetCommitHistory = getCommitsSinceLatestBeforeGivenDate(TARGET_DIR, reversedSourceCommitHistory[0].date);
 
     for (const sourceCommit of reversedSourceCommitHistory) {
         // "(Index of) First Target Commit that is earlier than (or equal to) the source commit"
         const targetCommitIndex = targetCommitHistory.findIndex(c => c.date <= sourceCommit.date);
         console.log(`DEBUG - targetCommitIndex: ${targetCommitIndex}. targetCommitHistory: ${JSON.stringify(targetCommitHistory)}`);
+        // TODO - refactor this to use guard clauses more than nested-ifs
         if (targetCommitIndex != -1) {
             const targetCommit = targetCommitHistory[targetCommitIndex];
             // If the target commit is a representation of the source commit, we can skip it
@@ -90,7 +67,7 @@ export async function main(sourceRepo: Repo, targetRepo: Repo, dryRun: boolean,
                     } else {
                         followOnTargetCommit = targetCommitHistory[targetCommitIndex - 1];
                     }
-                    insertRepresentativeCommit(sourceRepo, sourceCommit, targetCommit, followOnTargetCommit);
+                    insertRepresentativeCommit(TARGET_DIR,sourceRepoId, sourceCommit, targetCommit, followOnTargetCommit);
                     // And then regenerate the target commit history
                     // Thankfully, we only need to do this back to immediately preceding the _just processed_ source
                     // commit (since we know that all the rest of the source commits to be processed will be after it),
@@ -99,171 +76,44 @@ export async function main(sourceRepo: Repo, targetRepo: Repo, dryRun: boolean,
                     // compared), albeit approximately-halved - but I'm gambling on the fact that that should still take
                     // negligible practical time at usual repo sizes - at least, the ones I'm 
                     // this quadratic portion should be negligible, though - and, even if it isn't, it definitely will
-                    targetCommitHistory = buildTargetCommitHistory(TARGET_DIR, sourceCommit.date);
+                    targetCommitHistory = getCommitsSinceLatestBeforeGivenDate(TARGET_DIR, sourceCommit.date);
                 }
             }
             console.log(`DEBUG - targetCommit: ${targetCommit.hash}`);
         } else {
             console.log(`DEBUG - could not find a targetCommit that is earlier than or equal to the sourceCommit ${sourceCommit.hash} - therefore, writing the source commit's representation onto the current HEAD of target repo`);
-            insertRepresentativeCommit(sourceRepo, sourceCommit, undefined, undefined);
+            insertRepresentativeCommit(TARGET_DIR, sourceRepoId, sourceCommit, undefined, undefined);
             // As above, have to regenerate history after mutation
-            targetCommitHistory = buildTargetCommitHistory(TARGET_DIR, sourceCommit.date);
+            targetCommitHistory = getCommitsSinceLatestBeforeGivenDate(TARGET_DIR, sourceCommit.date);
         }
     }
     // OK, that's it - we've processed all the source commits, and we've inserted all the necessary target commits.
     // We can just `git push` to the target repo now.
-    //
-    // Note that it must be a `-f`, because we are literally rewriting history.
     if (!dryRun) {
-        execSync(`git push -f https://unused-username:${tokenForTargetRepo}@${targetRepo.domain}/${targetRepo.owner}/${targetRepo.name}`, {
+        gitPush(TARGET_DIR, tokenForTargetRepo, targetRepoId);
-            cwd: TARGET_DIR
-        })
-        // TODO - it'd be nice - before this `git push` is probably best - to add a `README.md` comment acknowledging
-        // the sync
     }
     return
-
 }
 
-export function buildSourceCommitHistory(path: string, numCommits: number): Commit[] {
+function setPreconditions(tokenForTargetRepo: string, sourceRepoId: RepoId, targetRepoId: RepoId) {
-    console.log(`DEBUG - building source commit history for ${path} with max count ${numCommits}`);
+    // It _shouldn't_ ever exist, but it if did, something weird is going on.
-    const output: Commit[] = [];
+    if (existsSync(WORKING_DIR) || existsSync(SOURCE_DIR) || existsSync(TARGET_DIR)) {
-
+        throw new Error('Working directory already exists/populated');
-    const logOutput = execSync(
-        // If you want to copy this formatting for debugging, it's:
-        //
-        // --pretty=format:'{"hash":"%h","author_name":"%an","author_email":"%ae","date":"%ai","message":"%s"}'
-        //
-        // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
-        // of string-parsing to consider here, I wouldn't want to bet without testing!
-        //eslint-disable-next-line no-useless-escape
-        `git log --max-count=${numCommits} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`,
-        { cwd: path }
-    );
-    const logLines = logOutput.toString().split('\n');
-    for (const line of logLines) {
-        const commit = parseCommit(path, line);
-        output.push(commit);
     }
 
-    return output;
+    if (tokenForTargetRepo == '') {
+        throw new Error('token_for_target_repo is required');
+    }
+
+    mkdirSync(WORKING_DIR);
+    mkdirSync(SOURCE_DIR);
+    mkdirSync(TARGET_DIR);
+
+    console.log(`DEBUG - sourceRepoPath: ${repoString(sourceRepoId)}`)
+    console.log(`DEBUG - targetRepoPath: ${repoString(targetRepoId)}`)
+
+    // TODO - allow parameterizing how far back in history to checkout (because it might take a long time for older
+    // repos and, once synced initially, it won't have to go back further than a single one in most cases)
+    gitClone(SOURCE_DIR, `https://${repoString(sourceRepoId)}`);
+    gitClone(TARGET_DIR, `https://${repoString(targetRepoId)}`);
 }
-
-export function buildTargetCommitHistory(path: string, oldestDateInSourceCommitHistory: Date): Commit[] {
-    console.log(`DEBUG - building target commit history for ${path} with oldest date ${oldestDateInSourceCommitHistory.toISOString()}`);
-    const output: Commit[] = [];
-
-    try {
-        const countingLogOutput = execSync(
-            `git log --since=${oldestDateInSourceCommitHistory.toISOString()} --pretty=oneline`,
-            { cwd: path }
-        );
-        const countedNumber = countingLogOutput.toString().split('\n').length;
-        console.log(`DEBUG - countedNumber (how many commits in target repo since oldest source commit) is: ${countedNumber}`);
-        // TODO - return to this and figure out if these are _actually_ "useless escapes" or not - got a couple layers
-        // of string-parsing to consider here, I wouldn't want to bet without testing!
-        const logOutput = execSync(
-            //eslint-disable-next-line no-useless-escape
-            `git log --max-count=${countedNumber+1} --pretty=format:'{\"hash\":\"%h\",\"author_name\":\"%an\",\"author_email\":\"%ae\",\"date\":\"%ai\",\"message\":\"%s\"}'`,
-            { cwd: path }
-        );
-        const logLines = logOutput.toString().split('\n');
-        for (const line of logLines) {
-            const commit = parseCommit(path, line);
-            output.push(commit);
-        }
-    } catch (e) {
-        const error = e as ExecSyncError
-        // Now you can safely access properties
-        // No commits in the target repo - return an empty array, which will result in the first representative commit 
-        // being made as the first commit. And then we can iterate as normal (recalling that the target history is 
-        // refreshed _from local repo_ - incurring no network charges) from there on.
-        const errorOutputAsString = '' + error.output[2]
-        if (!errorOutputAsString.includes('does not have any commits yet')) {
-            console.log(`Unexpected error: ${errorOutputAsString}`);
-            throw Error(`Unexpected error while building target commit history`, {
-                cause: error
-            })
-        }
-        // Fresh target repo - just write into it (by returning an empty array of target commits as target history)
-        // (i.e. doing nothing)
-    }
-    console.log(`As final output of buildTargetCommitHistory, preceding ${oldestDateInSourceCommitHistory.toISOString()}, output is ${JSON.stringify(output)}`);
-    return output;
-}
-
-// https://gist.github.com/textarcana/1306223
-function parseCommit(repo_path: string, line: string): Commit {
-    console.log(`DEBUG - line: ${line}, for path ${repo_path}`);
-    const parsed = JSON.parse(line)
-    return {
-        hash: parsed['hash'],
-        author_name: parsed['author_name'],
-        author_email: parsed['author_email'],
-        repo_path: repo_path,
-        date: new Date(parsed['date']),
-        message: parsed['message'],
-    }
-}
-
-function insertRepresentativeCommit(sourceRepo: Repo,sourceCommit: Commit, targetCommit: Commit | undefined, followOnTargetCommit: Commit | undefined): void {
-    // If there is a target commit,
-    if (targetCommit != undefined) {
-        execSync(`git reset --hard ${targetCommit.hash}`, {
-            cwd: TARGET_DIR
-        })
-    }
-
-    createRepresentativeCommit(sourceRepo, sourceCommit);
-    // Then, if there is a follow-on target commit, we need to cherry-pick it onto the source commit:
-    if (followOnTargetCommit != undefined) {
-        execSync(`git cherry-pick ${followOnTargetCommit.hash}`, {
-            cwd: TARGET_DIR
-        })
-    }// else - nothing to cherry-pick back on top
-    
-}
-
-function createRepresentativeCommit(sourceRepo: Repo,sourceCommit: Commit) {
-    // Create a commit that represents the source commit, but with a filename that is generated from the source commit's
-    // metadata.
-    //
-    // This is guaranteed to not cause conflicts with other commits, because the filename is generated from the source
-    // commit's metadata, and no two source commits will have the same metadata.
-    // (OK sure _technically_ these could have a collision, but...like...what are the odds?)
-    // TODO - figure out what the odds actually are, that'd be fun :P
-    const filename = `${sourceRepo.owner}/${sourceRepo.name}/${sourceCommit.hash}` 
-    mkdirSync(TARGET_DIR + '/' + sourceRepo.owner + '/' + sourceRepo.name, { recursive: true });
-    execSync(`touch ${filename}`, {
-        cwd: TARGET_DIR
-    })
-    execSync(`git add ${filename}`, {
-        cwd: TARGET_DIR
-    })
-
-    // Seems like setting `--author` on `git commit` is not sufficient - still need to set `user` as well (I guess those
-    // are the difference between `comitted by` and `written by`?)
-    // Confirmed by following the instructions [here](https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-github-profile/managing-contribution-settings-on-your-profile/why-are-my-contributions-not-showing-up-on-my-profile#your-local-git-commit-email-isnt-connected-to-your-account)
-    // to check the "made by" address, and confirming that it did not match the email set in the `--author` flag.
-    // Note that, contrary to advice given by the CLI, this does not use the global config, but the local one - because,
-    // otherwise, if this was run locally, it would mess up the host system's config.
-    execSync(`git config user.email "${sourceCommit.author_email}"`, { cwd: TARGET_DIR });
-    execSync(`git config user.name "${sourceCommit.author_name}"`, { cwd: TARGET_DIR });
-
-    try {
-        // Do _not_ arbitrarily remove the `hash` - it's used for signalling identity in `main()`
-        const args = `"${sourceRepo.owner}/${sourceRepo.name}: ${sourceCommit.message} - ${sourceCommit.hash}" --date="${format(sourceCommit.date, 'yyyy-MM-dd HH:mm:ss')}" --author="${sourceCommit.author_name} <${sourceCommit.author_email}>"`;
-        console.log(`About to commit with args ${args}`);
-        // https://github.com/Shpota/github-activity-generator/blob/main/contribute.py#L63
-        // "%Y-%m-%d %H:%M:%S"
-        execSync(`git commit -m ${args}`, {
-            cwd: TARGET_DIR
-        })
-    } catch (e) {
-        console.log(e);
-        const error = e as ExecSyncError;
-        console.log(`DEBUG - error while creating representative commit: ${'' + error.output[2]} ... ${'' + error.output[1]}`);
-        throw e;
-    }
-    
-}

src/types.ts

@@ -1,11 +1,11 @@
 // TODO - parametrize the scheme
-export type Repo = {
+export type RepoId = {
     domain: string;
     owner: string;
     name: string;
 }
 
-export function repoString(repo: Repo): string {
+export function repoString(repo: RepoId): string {
     return `${repo.domain}/${repo.owner}/${repo.name}`;
 }