support for node.x = y comments to add metadata, run over traverse too

hzoo · Sep 4, 2020 · 43b9022 · 43b9022
1 parent 170b2ba
commit 43b9022
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Showing 8 changed files with 84 additions and 27 deletions.
diff --git a/babel.config.js b/babel.config.js
@@ -133,7 +133,7 @@ module.exports = function (api) {
     ].filter(Boolean),
     overrides: [
       {
-        test: [/(babel-plugin|babel-helper)-/],
+        test: [/(babel-plugin|babel-helper|babel-traverse)/],
         plugins: [metadataPlugin],
       },
       {

diff --git a/packages/babel-plugin-proposal-numeric-separator/src/index.js b/packages/babel-plugin-proposal-numeric-separator/src/index.js
@@ -12,6 +12,7 @@ export default declare(api => {
       NumericLiteral({ node }) {
         const { extra } = node;
         if (extra && /_/.test(extra.raw)) {
+          // node: node
           extra.raw = extra.raw.replace(/_/g, "");
         }
       },

diff --git a/packages/babel-plugin-transform-block-scoping/src/index.js b/packages/babel-plugin-transform-block-scoping/src/index.js
@@ -147,6 +147,7 @@ function convertBlockScopedToVar(
     }
   }
 
+  // node: node
   node[t.BLOCK_SCOPED_SYMBOL] = true;
   node.kind = "var";
 

diff --git a/packages/babel-plugin-transform-property-literals/src/index.js b/packages/babel-plugin-transform-property-literals/src/index.js
@@ -17,6 +17,7 @@ export default declare(api => {
             !t.isValidES3Identifier(key.name)
           ) {
             // default: "bar" -> "default": "bar"
+            // node: node
             node.key = t.stringLiteral(key.name);
           }
         },

diff --git a/packages/babel-plugin-transform-shorthand-properties/src/index.js b/packages/babel-plugin-transform-shorthand-properties/src/index.js
@@ -26,6 +26,7 @@ export default declare(api => {
 
       ObjectProperty({ node }) {
         if (node.shorthand) {
+          // node: node
           node.shorthand = false;
         }
       },

diff --git a/packages/babel-traverse/src/scope/lib/renamer.js b/packages/babel-traverse/src/scope/lib/renamer.js
@@ -5,6 +5,7 @@ import * as t from "@babel/types";
 const renameVisitor = {
   ReferencedIdentifier({ node }, state) {
     if (node.name === state.oldName) {
+      // node: node
       node.name = state.newName;
     }
   },

diff --git a/sandbox/src/components/App.js b/sandbox/src/components/App.js
@@ -307,6 +307,7 @@ function CompiledOutput({
         }
       });
       gzipSize(code).then(s => setGzip(s));
+      window.ranges = ranges;
       setCompiled({
         code,
         size: new Blob([code], { type: "text/plain" }).size,

diff --git a/sandbox/src/metadataPlugin.js b/sandbox/src/metadataPlugin.js
@@ -1,19 +1,86 @@
 const path = require("path");
-function normalize(src) {
-  return src.replace(/\//, path.sep);
-}
+const BABEL_PACKAGES_REGEXP =
+  path.sep === "/" ? /packages\/(.*)/ : /packages\\(.*)/;
 
 module.exports = function babelPlugin(babel) {
   const { types: t, template } = babel;
 
+  function getMetaComment(path) {
+    /*
+      Allow specifying a node to get correct start/end
+      (instead of defaulting to this.node).
+
+      // node: rest
+      target.insertBefore(loop);
+    */
+    const hasComment = path.parentPath.node.leadingComments;
+    let comment;
+    if (hasComment && hasComment.length) {
+      comment = hasComment[hasComment.length - 1].value.match(/node: (.*)/);
+      if (comment) {
+        // remove the comment?
+        path.parentPath.node.leadingComments = [];
+        comment = template.expression(comment[1])();
+      }
+    }
+    return comment;
+  }
+
   return {
     name: "transform-babel-metadata",
+    pre(state) {
+      const filename =
+        state.opts.filename || "babel/packages/babel-plugin-custom/index.js";
+      this.filePath = filename.match(BABEL_PACKAGES_REGEXP)[1];
+      this.pluginName = this.filePath.match(/^[^(/|\\)]*/)[0];
+    },
     visitor: {
+      /*
+      node.babelPlugin = [{
+        name: "proposal-numeric-separator",
+        file: "proposal-numeric-separator\\src\\index.js (16:10)",
+        start: node.start,
+        end: node.end
+      }]
+      extra.raw = extra.raw.replace(/_/g, "");
+      */
+      AssignmentExpression(path, state) {
+        const comment = getMetaComment(path);
+        if (!comment) return;
+        const props = [
+          t.objectProperty(
+            t.identifier("name"),
+            t.stringLiteral(this.pluginName)
+          ),
+          t.objectProperty(
+            t.identifier("file"),
+            t.stringLiteral(
+              `${this.filePath} (${path.node.loc.start.line}:${path.node.loc.start.column})`
+            )
+          ),
+          t.objectProperty(
+            t.identifier("start"),
+            t.memberExpression(comment, t.identifier("start"))
+          ),
+          t.objectProperty(
+            t.identifier("end"),
+            t.memberExpression(comment, t.identifier("end"))
+          ),
+        ];
+        const metaNode = t.objectExpression(props);
+
+        path.insertBefore(
+          t.assignmentExpression(
+            "=",
+            t.memberExpression(comment, t.identifier("babelPlugin")),
+            t.arrayExpression([metaNode])
+          )
+        );
+      },
       // pathX.replaceWith(a) -> pathX.replaceWith(a, { name: "name" })
       // TODO: handle nested MemberExpression like a.b.replaceWith
       // TODO: CallExpression like path.get("left").replaceWith
       CallExpression(path, state) {
-        state.filename = state.filename || "babel-plugin-custom/src.js";
         if (
           path.node.callee.type === "MemberExpression" &&
           path.node.callee.property.type === "Identifier" &&
@@ -29,24 +96,7 @@ module.exports = function babelPlugin(babel) {
             (path.node.callee.object.type === "Identifier" &&
               path.node.callee.object.name) ||
             "path";
-          const pluginName = normalize(state.filename).match(
-            /babel-(plugin|helper)-((\w+-?)+)/
-          )[2];
-          /*
-            Allow specifying a node to get correct start/end
-            (instead of defaulting to this.node).
-
-            // node: rest
-            target.insertBefore(loop);
-          */
-          const hasComment = path.parentPath.node.leadingComments;
-          let comment;
-          if (hasComment && hasComment.length) {
-            comment = hasComment[0].value.match(/node: (.*)/);
-            if (comment) {
-              comment = template.expression(comment[1])();
-            }
-          }
+          const comment = getMetaComment(path);
           // "C:\\Users\\babel\\packages\\babel-plugin-proposal-unicode-property-regex\\src\\index.js".match(/babel-(plugin|helper)-((\w+-?)+)/)
           // {
           //   name: "unicode-property-regex",
@@ -55,13 +105,14 @@ module.exports = function babelPlugin(babel) {
           //   end: 1,
           // }
           const props = [
-            t.objectProperty(t.identifier("name"), t.stringLiteral(pluginName)),
+            t.objectProperty(
+              t.identifier("name"),
+              t.stringLiteral(this.pluginName)
+            ),
             t.objectProperty(
               t.identifier("file"),
               t.stringLiteral(
-                `${normalize(state.filename).substr(
-                  normalize(state.filename).indexOf(pluginName)
-                )} (${path.node.loc.start.line}:${path.node.loc.start.column})`
+                `${this.filePath} (${path.node.loc.start.line}:${path.node.loc.start.column})`
               )
             ),
           ];