Rewrite changelog script from Bash to JavaScript (#10782)

The `auto-changelog` script has been rewritten from Bash to JavaScript.
Functionally it should behave identically.

development/auto-changelog.js

@@ -0,0 +1,86 @@
+#!/usr/bin/env node
+const fs = require('fs').promises;
+const path = require('path');
+const runCommand = require('./lib/runCommand');
+
+const URL = 'https://github.com/MetaMask/metamask-extension';
+
+async function main() {
+  await runCommand('git', ['fetch', '--tags']);
+
+  const [mostRecentTagCommitHash] = await runCommand('git', [
+    'rev-list',
+    '--tags',
+    '--max-count=1',
+  ]);
+  const [mostRecentTag] = await runCommand('git', [
+    'describe',
+    '--tags',
+    mostRecentTagCommitHash,
+  ]);
+
+  const commitsSinceLastRelease = await runCommand('git', [
+    'rev-list',
+    `${mostRecentTag}..HEAD`,
+  ]);
+
+  const changelogEntries = [];
+  for (const commit of commitsSinceLastRelease) {
+    const [subject] = await runCommand('git', [
+      'show',
+      '-s',
+      '--format=%s',
+      commit,
+    ]);
+
+    let prefix;
+    let description = subject;
+
+    // Squash & Merge: the commit subject is parsed as `<description> (#<PR ID>)`
+    if (subject.match(/\(#\d+\)/u)) {
+      const [, prNumber] = subject.match(/\(#(\d+)\)/u);
+      prefix = `[#${prNumber}](${URL}/pull/${prNumber})`;
+      description = subject.match(/^(.+)\s\(#\d+\)/u)[1];
+      // Merge: the PR ID is parsed from the git subject (which is of the form `Merge pull request
+      // #<PR ID> from <branch>`, and the description is assumed to be the first line of the body.
+      // If no body is found, the description is set to the commit subject
+    } else if (subject.match(/#\d+\sfrom/u)) {
+      const [, prNumber] = subject.match(/#(\d+)\sfrom/u);
+      prefix = `[#${prNumber}](${URL}/pull/${prNumber})`;
+      const [firstLineOfBody] = await runCommand('git', [
+        'show',
+        '-s',
+        '--format=%b',
+        commit,
+      ]);
+      description = firstLineOfBody || subject;
+    }
+    // Otherwise:
+    // Normal commits: The commit subject is the description, and the PR ID is omitted.
+
+    const changelogEntry = prefix
+      ? `- ${prefix}: ${description}`
+      : `- ${description}`;
+    changelogEntries.push(changelogEntry);
+  }
+
+  const changelogFilename = path.resolve(__dirname, '..', 'CHANGELOG.md');
+  const changelog = await fs.readFile(changelogFilename, { encoding: 'utf8' });
+  const changelogLines = changelog.split('\n');
+  const releaseHeaderIndex = changelogLines.findIndex(
+    (line) => line === '## Current Develop Branch',
+  );
+  if (releaseHeaderIndex === -1) {
+    throw new Error('Failed to find release header');
+  }
+  changelogLines.splice(releaseHeaderIndex + 1, 0, ...changelogEntries);
+  const updatedChangelog = changelogLines.join('\n');
+  await fs.writeFile(changelogFilename, updatedChangelog);
+
+  console.log('CHANGELOG updated');
+}
+
+main().catch((error) => {
+  console.error(error);
+  process.exit(1);
+});

development/auto-changelog.sh

@@ -1,60 +0,0 @@
-#!/usr/bin/env bash
-
-set -e
-set -u
-set -o pipefail
-
-readonly URL='https://github.com/MetaMask/metamask-extension'
-
-git fetch --tags
-
-most_recent_tag="$(git describe --tags "$(git rev-list --tags --max-count=1)")"
-
-git rev-list "${most_recent_tag}"..HEAD | while read -r commit
-do
-    subject="$(git show -s --format="%s" "$commit")"
-
-    # Squash & Merge: the commit subject is parsed as `<description> (#<PR ID>)`
-    if grep -E -q '\(#[[:digit:]]+\)' <<< "$subject"
-    then
-        pr="$(awk '{print $NF}' <<< "$subject" | tr -d '()')"
-        prefix="[$pr]($URL/pull/${pr###}): "
-        description="$(awk '{NF--; print $0}' <<< "$subject")"
-
-    # Merge: the PR ID is parsed from the git subject (which is of the form `Merge pull request
-    #   #<PR ID> from <branch>`, and the description is assumed to be the first line of the body.
-    #   If no body is found, the description is set to the commit subject
-    elif grep -E -q '#[[:digit:]]+\sfrom' <<< "$subject"
-    then
-        pr="$(awk '{print $4}' <<< "$subject")"
-        prefix="[$pr]($URL/pull/${pr###}): "
-
-        first_line_of_body="$(git show -s --format="%b" "$commit" | head -n 1 | tr -d '\r')"
-        if [[ -z "$first_line_of_body" ]]
-        then
-            description="$subject"
-        else
-            description="$first_line_of_body"
-        fi
-
-    # Normal commits: The commit subject is the description, and the PR ID is omitted.
-    else
-        pr=''
-        prefix=''
-        description="$subject"
-    fi
-
-    # add entry to CHANGELOG
-    if [[ "$OSTYPE" == "linux-gnu" ]]
-    then
-        # shellcheck disable=SC1004
-        sed -i'' '/## Current Develop Branch/a\
-- '"$prefix$description"''$'\n' CHANGELOG.md
-    else
-        # shellcheck disable=SC1004
-        sed -i '' '/## Current Develop Branch/a\
-- '"$prefix$description"''$'\n' CHANGELOG.md
-    fi
-done
-
-echo 'CHANGELOG updated'

development/lib/runCommand.js

@@ -0,0 +1,79 @@
+const spawn = require('cross-spawn');
+
+/**
+ * Run a command to completion using the system shell.
+ *
+ * This will run a command with the specified arguments, and resolve when the
+ * process has exited. The STDOUT stream is monitored for output, which is
+ * returned after being split into lines. All output is expected to be UTF-8
+ * encoded, and empty lines are removed from the output.
+ *
+ * Anything received on STDERR is assumed to indicate a problem, and is tracked
+ * as an error.
+ *
+ * @param {string} command - The command to run
+ * @param {Array<string>} [args] - The arguments to pass to the command
+ * @returns {Array<string>} Lines of output received via STDOUT
+ */
+async function runCommand(command, args) {
+  const output = [];
+  let mostRecentError;
+  let errorSignal;
+  let errorCode;
+  const internalError = new Error('Internal');
+  try {
+    await new Promise((resolve, reject) => {
+      const childProcess = spawn(command, args, { encoding: 'utf8' });
+      childProcess.stdout.setEncoding('utf8');
+      childProcess.stderr.setEncoding('utf8');
+
+      childProcess.on('error', (error) => {
+        mostRecentError = error;
+      });
+
+      childProcess.stdout.on('data', (message) => {
+        const nonEmptyLines = message.split('\n').filter((line) => line !== '');
+        output.push(...nonEmptyLines);
+      });
+
+      childProcess.stderr.on('data', (message) => {
+        mostRecentError = new Error(message.trim());
+      });
+
+      childProcess.once('exit', (code, signal) => {
+        if (code === 0) {
+          return resolve();
+        }
+        errorCode = code;
+        errorSignal = signal;
+        return reject(internalError);
+      });
+    });
+  } catch (error) {
+    /**
+     * The error is re-thrown here in an `async` context to preserve the stack trace. If this was
+     * was thrown inside the Promise constructor, the stack trace would show a few frames of
+     * Node.js internals then end, without indicating where `runCommand` was called.
+     */
+    if (error === internalError) {
+      let errorMessage;
+      if (errorCode !== null && errorSignal !== null) {
+        errorMessage = `Terminated by signal '${errorSignal}'; exited with code '${errorCode}'`;
+      } else if (errorSignal !== null) {
+        errorMessage = `Terminaled by signal '${errorSignal}'`;
+      } else if (errorCode === null) {
+        errorMessage = 'Exited with no code or signal';
+      } else {
+        errorMessage = `Exited with code '${errorCode}'`;
+      }
+      const improvedError = new Error(errorMessage);
+      if (mostRecentError) {
+        improvedError.cause = mostRecentError;
+      }
+      throw improvedError;
+    }
+  }
+  return output;
+}
+
+module.exports = runCommand;

package.json

@@ -53,7 +53,7 @@
     "storybook": "start-storybook -p 6006 -c .storybook --static-dir ./app ./storybook/images",
     "storybook:build": "build-storybook -c .storybook -o storybook-build --static-dir ./app ./storybook/images",
     "storybook:deploy": "storybook-to-ghpages --existing-output-dir storybook-build --remote storybook --branch master",
-    "update-changelog": "./development/auto-changelog.sh",
+    "update-changelog": "node ./development/auto-changelog.js",
     "generate:migration": "./development/generate-migration.sh",
     "lavamoat:auto": "lavamoat ./development/build/index.js --writeAutoPolicy",
     "lavamoat:debug": "lavamoat ./development/build/index.js --writeAutoPolicyDebug"