Detect and apply stripping flow types (#1864)

parcel-bundler · Aug 23, 2018 · 7a5f51c · 7a5f51c
1 parent a789305
commit 7a5f51c
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Showing 7 changed files with 65 additions and 4 deletions.
diff --git a/packages/core/parcel-bundler/package.json b/packages/core/parcel-bundler/package.json
@@ -20,6 +20,7 @@
     "babel-core": "^6.25.0",
     "babel-generator": "^6.25.0",
     "babel-plugin-transform-es2015-modules-commonjs": "^6.26.0",
+    "babel-plugin-transform-flow-strip-types": "^6.22.0",
     "babel-plugin-transform-object-rest-spread": "^6.26.0",
     "babel-plugin-transform-react-jsx": "^6.24.1",
     "babel-preset-env": "^1.7.0",

diff --git a/packages/core/parcel-bundler/src/Bundler.js b/packages/core/parcel-bundler/src/Bundler.js
@@ -251,9 +251,7 @@ class Bundler extends EventEmitter {
             this.entryAssets.add(asset);
           } catch (err) {
             throw new Error(
-              `Cannot resolve entry "${entry}" from "${
-                this.options.rootDir
-              }"`
+              `Cannot resolve entry "${entry}" from "${this.options.rootDir}"`
             );
           }
         }

diff --git a/packages/core/parcel-bundler/src/transforms/babel.js b/packages/core/parcel-bundler/src/transforms/babel.js
@@ -103,6 +103,7 @@ async function getBabelConfig(asset) {
 
   let envConfig = await getEnvConfig(asset, isSource);
   let jsxConfig = await getJSXConfig(asset, isSource);
+  let flowConfig = getFlowConfig(asset, isSource);
 
   // Merge the babel-preset-env config and the babelrc if needed
   if (babelrc && !shouldIgnoreBabelrc(asset.name, babelrc)) {
@@ -134,12 +135,21 @@ async function getBabelConfig(asset) {
       mergeConfigs(babelrc, jsxConfig);
     }
 
+    // Add Flow stripping config if it isn't already specified in the babelrc
+    let hasFlow = hasPlugin(babelrc.plugins, 'transform-flow-strip-types');
+
+    if (!hasFlow && flowConfig) {
+      mergeConfigs(babelrc, flowConfig);
+    }
+
     return babelrc;
   }
 
   // If there is a babel-preset-env config, and it isn't empty use that
-  if (envConfig && (envConfig.plugins.length > 0 || jsxConfig)) {
+  if (envConfig && (envConfig.plugins.length > 0 || jsxConfig || flowConfig)) {
     mergeConfigs(envConfig, jsxConfig);
+    mergeConfigs(envConfig, flowConfig);
+
     return envConfig;
   }
 
@@ -148,6 +158,11 @@ async function getBabelConfig(asset) {
     return jsxConfig;
   }
 
+  // If there is a Flow config, return that
+  if (flowConfig) {
+    return flowConfig;
+  }
+
   // Otherwise, don't run babel at all
   return null;
 }
@@ -309,3 +324,17 @@ async function getJSXConfig(asset, isSourceModule) {
     };
   }
 }
+
+/**
+ * Generates a babel config for stripping away Flow types.
+ */
+function getFlowConfig(asset) {
+  if (/^(\/{2}|\/\*+) *@flow/.test(asset.contents.substring(0, 20))) {
+    return {
+      plugins: [[require('babel-plugin-transform-flow-strip-types')]],
+      internal: true
+    };
+  }
+
+  return null;
+}
diff --git a/packages/core/parcel-bundler/test/integration/babel-strip-flow-types/index.js b/packages/core/parcel-bundler/test/integration/babel-strip-flow-types/index.js
@@ -0,0 +1,5 @@
+const flowModule = require('flow-typed');
+
+module.exports = function() {
+  return flowModule();
+}
diff --git a/...e/parcel-bundler/test/integration/babel-strip-flow-types/node_modules/flow-typed/index.js b/...e/parcel-bundler/test/integration/babel-strip-flow-types/node_modules/flow-typed/index.js
diff --git a/packages/core/parcel-bundler/test/javascript.js b/packages/core/parcel-bundler/test/javascript.js
@@ -1379,4 +1379,17 @@ describe('javascript', function() {
     assert(output.includes('<html>'));
     assert(output.includes('Other page'));
   });
+
+  it('should strip away flow types of node modules', async function() {
+    let b = await bundle(
+      __dirname + '/integration/babel-strip-flow-types/index.js'
+    );
+
+    let output = await run(b);
+    assert.equal(typeof output, 'function');
+    assert.equal(output(), 'hello world');
+
+    let file = await fs.readFile(__dirname + '/dist/index.js', 'utf8');
+    assert(!file.includes('OptionsType'));
+  });
 });
diff --git a/yarn.lock b/yarn.lock
@@ -523,6 +523,10 @@ babel-plugin-syntax-exponentiation-operator@^6.8.0:
   version "6.13.0"
   resolved "https://registry.yarnpkg.com/babel-plugin-syntax-exponentiation-operator/-/babel-plugin-syntax-exponentiation-operator-6.13.0.tgz#9ee7e8337290da95288201a6a57f4170317830de"
 
+babel-plugin-syntax-flow@^6.18.0:
+  version "6.18.0"
+  resolved "https://artifactory.corp.adobe.com:443/artifactory/api/npm/npm-livefyre-release/babel-plugin-syntax-flow/-/babel-plugin-syntax-flow-6.18.0.tgz#4c3ab20a2af26aa20cd25995c398c4eb70310c8d"
+
 babel-plugin-syntax-jsx@^6.8.0:
   version "6.18.0"
   resolved "https://registry.yarnpkg.com/babel-plugin-syntax-jsx/-/babel-plugin-syntax-jsx-6.18.0.tgz#0af32a9a6e13ca7a3fd5069e62d7b0f58d0d8946"
@@ -725,6 +729,13 @@ babel-plugin-transform-exponentiation-operator@^6.22.0:
     babel-plugin-syntax-exponentiation-operator "^6.8.0"
     babel-runtime "^6.22.0"
 
+babel-plugin-transform-flow-strip-types@^6.22.0:
+  version "6.22.0"
+  resolved "https://artifactory.corp.adobe.com:443/artifactory/api/npm/npm-livefyre-release/babel-plugin-transform-flow-strip-types/-/babel-plugin-transform-flow-strip-types-6.22.0.tgz#84cb672935d43714fdc32bce84568d87441cf7cf"
+  dependencies:
+    babel-plugin-syntax-flow "^6.18.0"
+    babel-runtime "^6.22.0"
+
 babel-plugin-transform-object-rest-spread@^6.26.0:
   version "6.26.0"
   resolved "https://registry.yarnpkg.com/babel-plugin-transform-object-rest-spread/-/babel-plugin-transform-object-rest-spread-6.26.0.tgz#0f36692d50fef6b7e2d4b3ac1478137a963b7b06"