Add git node staging command

components/git/staging.js

@@ -0,0 +1,105 @@
+import CLI from '../../lib/cli.js';
+import { runPromise } from '../../lib/run.js';
+import { Staging } from '../../lib/staging.js';
+
+export const command = 'staging';
+export const describe = 'Automatic port commits to a release line branch';
+
+const stagingOptions = {
+  autoSkip: {
+    describe: 'Automatically skip commits with conflicts that have to be manually resolved',
+    type: 'boolean'
+  },
+  backport: {
+    describe: 'The PR ID / number to backport, skip staging commits',
+    type: 'number'
+  },
+  continue: {
+    describe: 'Continue the staging process after a conflict',
+    type: 'boolean'
+  },
+  paginate: {
+    describe: 'Sets a maximum number of commits to port',
+    type: 'number'
+  },
+  releaseLine: {
+    describe: 'The major version of the target release',
+    type: 'number'
+  },
+  reportDestination: {
+    describe: 'The destination to write the report to. Possible values are: ' +
+      'stdout, github, or a file path, defaults to an interactive prompt.',
+    type: 'string',
+    default: undefined
+  },
+  reporter: {
+    describe: 'The reporter to use for the output',
+    type: 'string',
+    default: 'markdown'
+  },
+  reset: {
+    describe: 'Reset the staging process',
+    type: 'boolean'
+  },
+  skip: {
+    describe: 'Continue the staging process marking the current commit as skipped',
+    type: 'boolean'
+  },
+  skipGH: {
+    describe: 'Skip all `gh` cli actions. Will not read / add label to GitHub PRs',
+    type: 'boolean'
+  }
+};
+
+export function builder(yargs) {
+  return yargs
+    .options(stagingOptions)
+    .example('git node staging --releaseLine=23',
+      'Port commits to the v1.x-staging branch');
+}
+
+export function handler(argv) {
+  const logStream = process.stdout.isTTY ? process.stdout : process.stderr;
+  const cli = new CLI(logStream);
+  const dir = process.cwd();
+
+  return runPromise(main(argv, cli, dir)).catch((err) => {
+    if (cli.spinner.enabled) {
+      cli.spinner.fail();
+    }
+    throw err;
+  });
+}
+
+async function main(argv, cli, dir) {
+  const {
+    autoSkip,
+    backport,
+    paginate,
+    releaseLine,
+    reportDestination,
+    reporter,
+    reset,
+    skip,
+    skipGH
+  } = argv;
+  const staging = new Staging({
+    cli,
+    dir,
+    cont: argv.continue,
+    autoSkip,
+    paginate,
+    releaseLine,
+    reportDestination,
+    reporter,
+    skip,
+    skipGH
+  });
+  if (backport) {
+    await staging.requestBackport(backport);
+  } else if (reset) {
+    await staging.reset();
+  } else {
+    await staging.run();
+  }
+}

lib/cli.js

@@ -107,6 +107,11 @@
   }
 
   stopSpinner(rawText, status = SUCCESS) {
+    if (!rawText) {
+      this.spinner.stop();
+      return;
+    }
+
     let symbol;
     switch (status) {
       case SUCCESS:

lib/prepare_release.js

@@ -523,12 +523,24 @@ export default class ReleasePreparation extends Session {
     const { newVersion } = this;
     const proposalBranch = `v${newVersion}-proposal`;
 
-    await runAsync('git', [
-      'checkout',
-      '-b',
-      proposalBranch,
-      base
-    ]);
+    try {
+      await forceRunAsync('git', [
+        'checkout',
+        '-b',
+        proposalBranch,
+        base
+      ], { captureStdout: true, captureStderr: true, ignoreFailures: false });
+    } catch (err) {
+      const branchExistsRE = /fatal: a branch named '.*' already exists/i;
+      if (branchExistsRE.test(err.stderr)) {
+        await runAsync('git', [
+          'checkout',
+          proposalBranch
+        ]);
+      } else {
+        throw err;
+      }
+    }
     return proposalBranch;
   }
 

lib/run.js

@@ -12,14 +12,19 @@
   ignoreFailure = true,
   spawnArgs,
   input,
-  captureStdout = false
+  captureStdout = false,
+  captureStderr = false
 } = {}) {
   if (cmd instanceof URL) {
     cmd = fileURLToPath(cmd);
   }
   let stdio = 'inherit';
   if (captureStdout || input != null) {
-    stdio = [input == null ? 'inherit' : 'pipe', captureStdout ? 'pipe' : 'inherit', 'inherit'];
+    stdio = [
+      input == null ? 'inherit' : 'pipe',
+      captureStdout ? 'pipe' : 'inherit',
+      captureStderr ? 'pipe' : 'inherit'
+    ];
   }
   return new Promise((resolve, reject) => {
     const opt = Object.assign({
@@ -36,13 +41,22 @@
       child.stdout.setEncoding('utf8');
       child.stdout.on('data', (chunk) => { stdout += chunk; });
     }
+    let stderr;
+    if (captureStderr) {
+      stderr = '';
+      child.stderr.setEncoding('utf8');
+      child.stderr.on('data', (chunk) => { stderr += chunk; });
+    }
     child.on('error', reject);
     child.on('close', (code) => {
       if (code !== 0) {
         if (ignoreFailure) {
           return reject(new Error(IGNORE));
         }
         const err = new Error(`${cmd} ${args} failed: ${code}`);
+        if (stderr) {
+          err.stderr = stderr;
+        }
         err.code = code;
         err.messageOnly = true;
         return reject(err);