Run Flow for each renderer separately (#12846)

* Generate Flow config on install

We'll need to do pre-renderer Flow passes with different configs.
This is the first step to get it working. We only want the original version checked in.

* Create multiple Flow configs from a template

* Run Flow per renderer

* Lint

* Revert the environment consolidation

I thought this would be a bit cleaner at first because we now have non-environment files in this directory.
But Sebastian is changing these files at the same time so I want to avoid conflicts and keep the PR more tightly scoped. Undo.

* Misc

.gitignore

@@ -1,5 +1,6 @@
 .DS_STORE
 node_modules
+scripts/flow/*/.flowconfig
 *~
 *.pyc
 .grunt
@@ -21,4 +22,4 @@ chrome-user-data
 *.iml
 .vscode
 *.swp
-*.swo
+*.swo

package.json

@@ -110,7 +110,7 @@
     "linc": "node ./scripts/tasks/linc.js",
     "lint": "node ./scripts/tasks/eslint.js",
     "lint-build": "node ./scripts/rollup/validate/index.js",
-    "postinstall": "node node_modules/fbjs-scripts/node/check-dev-engines.js package.json",
+    "postinstall": "node node_modules/fbjs-scripts/node/check-dev-engines.js package.json && node ./scripts/flow/createFlowConfigs.js",
     "debug-test": "cross-env NODE_ENV=development node --inspect-brk node_modules/.bin/jest --config ./scripts/jest/config.source.js --runInBand",
     "test": "cross-env NODE_ENV=development jest --config ./scripts/jest/config.source.js",
     "test-prod": "cross-env NODE_ENV=production jest --config ./scripts/jest/config.source.js",

.flowconfig → scripts/flow/config/flowconfig

@@ -1,25 +1,26 @@
 [ignore]
-
-<PROJECT_ROOT>/fixtures/.*
-<PROJECT_ROOT>/build/.*
-<PROJECT_ROOT>/scripts/bench/.*
+.*/scripts/bench/.*
 
 # These shims are copied into external projects:
-<PROJECT_ROOT>/scripts/rollup/shims/facebook-www/.*
-<PROJECT_ROOT>/scripts/rollup/shims/react-native/.*
+.*/rollup/shims/facebook-www/.*
+.*/rollup/shims/react-native/.*
 
-<PROJECT_ROOT>/.*/node_modules/y18n/.*
-<PROJECT_ROOT>/node_modules/chrome-devtools-frontend/.*
-<PROJECT_ROOT>/node_modules/devtools-timeline-model/.*
-<PROJECT_ROOT>/node_modules/create-react-class/.*
-<PROJECT_ROOT>/.*/__mocks__/.*
-<PROJECT_ROOT>/.*/__tests__/.*
+.*/node_modules/y18n/.*
+.*/node_modules/chrome-devtools-frontend/.*
+.*/node_modules/devtools-timeline-model/.*
+.*/node_modules/create-react-class/.*
+.*/__mocks__/.*
+.*/__tests__/.*
 
 [include]
+../../../node_modules/
+../../../packages/
+../../../scripts/
 
 [libs]
-./node_modules/fbjs/flow/lib/dev.js
-./scripts/flow
+../../../node_modules/fbjs/flow/lib/dev.js
+../environment.js
+../react-native-host-hooks.js
 
 [lints]
 untyped-type-import=error
@@ -42,4 +43,4 @@ suppress_comment=\\(.\\|\n\\)*\\$FlowFixedInNextDeploy
 suppress_comment=\\(.\\|\n\\)*\\$FlowExpectedError
 
 [version]
-^0.61.0
+^0.61.0

scripts/flow/createFlowConfigs.js

@@ -0,0 +1,44 @@
+'use strict';
+
+const chalk = require('chalk');
+const fs = require('fs');
+const mkdirp = require('mkdirp');
+const {typedRenderers} = require('./typedRenderers');
+
+const config = fs.readFileSync(__dirname + '/config/flowconfig');
+
+function writeConfig(folder) {
+  mkdirp.sync(folder);
+
+  const disclaimer = `
+# ---------------------------------------------------------------#
+# NOTE: this file is generated.                                  #
+# If you want to edit it, open ./scripts/flow/config/flowconfig. #
+# Then run Yarn for changes to take effect.                      #
+# ---------------------------------------------------------------#
+  `.trim();
+
+  const configFile = folder + '/.flowconfig';
+  let oldConfig;
+  try {
+    oldConfig = fs.readFileSync(configFile).toString();
+  } catch (err) {
+    oldConfig = null;
+  }
+  const newConfig = `
+${disclaimer}
+${config}
+${disclaimer}
+`.trim();
+
+  if (newConfig !== oldConfig) {
+    fs.writeFileSync(configFile, newConfig);
+    console.log(chalk.dim('Wrote a Flow config to ' + configFile));
+  }
+}
+
+// Write multiple configs in different folders
+// so that we can run those checks in parallel if we want.
+typedRenderers.forEach(renderer => {
+  writeConfig(__dirname + '/' + renderer);
+});

scripts/flow/runFlow.js

@@ -0,0 +1,37 @@
+'use strict';
+
+const chalk = require('chalk');
+const spawn = require('child_process').spawn;
+const extension = process.platform === 'win32' ? '.cmd' : '';
+
+require('./createFlowConfigs');
+
+async function runFlow(renderer, args) {
+  return new Promise(resolve => {
+    console.log(
+      'Running Flow for the ' + chalk.cyan(renderer) + ' renderer...',
+    );
+    spawn('../../../node_modules/.bin/flow' + extension, args, {
+      // Allow colors to pass through:
+      stdio: 'inherit',
+      // Use a specific renderer config:
+      cwd: process.cwd() + '/scripts/flow/' + renderer + '/',
+    }).on('close', function(code) {
+      if (code !== 0) {
+        console.error(
+          'Flow failed for the ' + chalk.red(renderer) + ' renderer',
+        );
+        console.log();
+        process.exit(code);
+      } else {
+        console.log(
+          'Flow passed for the ' + chalk.green(renderer) + ' renderer',
+        );
+        console.log();
+        resolve();
+      }
+    });
+  });
+}
+
+module.exports = runFlow;

scripts/flow/typedRenderers.js

@@ -0,0 +1,3 @@
+'use strict';
+
+exports.typedRenderers = ['dom', 'fabric', 'native', 'test'];

scripts/tasks/flow-ci.js

@@ -7,23 +7,18 @@
 
 'use strict';
 
-const path = require('path');
-const spawn = require('child_process').spawn;
-
-const extension = process.platform === 'win32' ? '.cmd' : '';
+process.on('unhandledRejection', err => {
+  throw err;
+});
 
-// This script forces a complete check.
-// Use it for the CI.
+const runFlow = require('../flow/runFlow');
+const {typedRenderers} = require('../flow/typedRenderers');
 
-spawn(path.join('node_modules', '.bin', 'flow' + extension), ['check', '.'], {
-  // Allow colors to pass through
-  stdio: 'inherit',
-}).on('close', function(code) {
-  if (code !== 0) {
-    console.error('Flow failed');
-  } else {
-    console.log('Flow passed');
+async function checkAll() {
+  // eslint-disable-next-line no-for-of-loops/no-for-of-loops
+  for (let renderer of typedRenderers) {
+    await runFlow(renderer, ['check']);
   }
+}
 
-  process.exit(code);
-});
+checkAll();

scripts/tasks/flow.js

@@ -7,23 +7,42 @@
 
 'use strict';
 
-const path = require('path');
-const spawn = require('child_process').spawn;
+process.on('unhandledRejection', err => {
+  throw err;
+});
 
-const extension = process.platform === 'win32' ? '.cmd' : '';
+const chalk = require('chalk');
+const runFlow = require('../flow/runFlow');
+const {typedRenderers} = require('../flow/typedRenderers');
 
 // This script is using `flow status` for a quick check with a server.
 // Use it for local development.
 
-spawn(path.join('node_modules', '.bin', 'flow' + extension), ['status', '.'], {
-  // Allow colors to pass through
-  stdio: 'inherit',
-}).on('close', function(code) {
-  if (code !== 0) {
-    console.error('Flow failed');
-  } else {
-    console.log('Flow passed');
-  }
+const primaryRenderer = process.argv[2];
+if (typedRenderers.indexOf(primaryRenderer) === -1) {
+  console.log(
+    'The ' +
+      chalk.red('yarn flow') +
+      ' command now requires you to pick a primary renderer:'
+  );
+  console.log();
+  typedRenderers.forEach(renderer => {
+    console.log('  * ' + chalk.cyan('yarn flow ' + renderer));
+  });
+  console.log();
+  console.log('If you are not sure, run ' + chalk.green('yarn flow dom') + '.');
+  console.log(
+    'This will still typecheck non-DOM packages, although less precisely.'
+  );
+  console.log();
+  console.log('Note that checks for all renderers will run on CI.');
+  console.log(
+    'You can also do this locally with ' +
+      chalk.cyan('yarn flow-ci') +
+      ' but it will be slow.'
+  );
+  console.log();
+  process.exit(1);
+}
 
-  process.exit(code);
-});
+runFlow(primaryRenderer, ['status']);