@babel-core: parse should parse only (#10914)

* @babel/core: parse methods should parse only

* Update Flow types

packages/babel-core/src/parse.js

@@ -1,14 +1,11 @@
 // @flow
 
 import loadConfig, { type InputOptions } from "./config";
-import normalizeFile from "./transformation/normalize-file";
+import parser from "./parser";
+import type { ParseResult } from "./parser";
 import normalizeOptions from "./transformation/normalize-opts";
 
-type AstRoot = BabelNodeFile | BabelNodeProgram;
-
-export type ParseResult = AstRoot;
-
-export type FileParseCallback = {
+type FileParseCallback = {
   (Error, null): any,
   (null, ParseResult | null): any,
 };
@@ -49,7 +46,7 @@ export const parse: Parse = (function parse(code, opts, callback) {
       const cfg = loadConfig(opts);
       if (cfg === null) return cb(null, null);
 
-      ast = normalizeFile(cfg.passes, normalizeOptions(cfg), code).ast;
+      ast = parser(cfg.passes, normalizeOptions(cfg), code);
     } catch (err) {
       return cb(err);
     }
@@ -68,7 +65,7 @@ export function parseSync(
     return null;
   }
 
-  return normalizeFile(config.passes, normalizeOptions(config), code).ast;
+  return parser(config.passes, normalizeOptions(config), code);
 }
 
 export function parseAsync(

packages/babel-core/src/parser/index.js

@@ -0,0 +1,74 @@
+import { parse } from "@babel/parser";
+import { codeFrameColumns } from "@babel/code-frame";
+import generateMissingPluginMessage from "./util/missing-plugin-helper";
+
+type AstRoot = BabelNodeFile | BabelNodeProgram;
+
+export type ParseResult = AstRoot;
+
+export default function parser(
+  pluginPasses: PluginPasses,
+  { parserOpts, highlightCode = true, filename = "unknown" }: Object,
+  code: string,
+): ParseResult {
+  try {
+    const results = [];
+    for (const plugins of pluginPasses) {
+      for (const plugin of plugins) {
+        const { parserOverride } = plugin;
+        if (parserOverride) {
+          const ast = parserOverride(code, parserOpts, parse);
+
+          if (ast !== undefined) results.push(ast);
+        }
+      }
+    }
+
+    if (results.length === 0) {
+      return parse(code, parserOpts);
+    } else if (results.length === 1) {
+      if (typeof results[0].then === "function") {
+        throw new Error(
+          `You appear to be using an async parser plugin, ` +
+            `which your current version of Babel does not support. ` +
+            `If you're using a published plugin, you may need to upgrade ` +
+            `your @babel/core version.`,
+        );
+      }
+      return results[0];
+    }
+    throw new Error("More than one plugin attempted to override parsing.");
+  } catch (err) {
+    if (err.code === "BABEL_PARSER_SOURCETYPE_MODULE_REQUIRED") {
+      err.message +=
+        "\nConsider renaming the file to '.mjs', or setting sourceType:module " +
+        "or sourceType:unambiguous in your Babel config for this file.";
+      // err.code will be changed to BABEL_PARSE_ERROR later.
+    }
+
+    const { loc, missingPlugin } = err;
+    if (loc) {
+      const codeFrame = codeFrameColumns(
+        code,
+        {
+          start: {
+            line: loc.line,
+            column: loc.column + 1,
+          },
+        },
+        {
+          highlightCode,
+        },
+      );
+      if (missingPlugin) {
+        err.message =
+          `${filename}: ` +
+          generateMissingPluginMessage(missingPlugin[0], loc, codeFrame);
+      } else {
+        err.message = `${filename}: ${err.message}\n\n` + codeFrame;
+      }
+      err.code = "BABEL_PARSE_ERROR";
+    }
+    throw err;
+  }
+}

packages/babel-core/src/transformation/normalize-file.js

@@ -7,10 +7,8 @@ import cloneDeep from "lodash/cloneDeep";
 import * as t from "@babel/types";
 import type { PluginPasses } from "../config";
 import convertSourceMap, { typeof Converter } from "convert-source-map";
-import { parse } from "@babel/parser";
-import { codeFrameColumns } from "@babel/code-frame";
 import File from "./file/file";
-import generateMissingPluginMessage from "./util/missing-plugin-helper";
+import parser from "../parser";
 
 const debug = buildDebug("babel:transform:file");
 const LARGE_INPUT_SOURCEMAP_THRESHOLD = 1_000_000;
@@ -37,9 +35,6 @@ export default function normalizeFile(
     }
     ast = cloneDeep(ast);
   } else {
-    // The parser's AST types aren't fully compatible with the types generated
-    // by the logic in babel-types.
-    // $FlowFixMe
     ast = parser(pluginPasses, options, code);
   }
 
@@ -94,73 +89,6 @@ export default function normalizeFile(
   });
 }
 
-function parser(
-  pluginPasses: PluginPasses,
-  { parserOpts, highlightCode = true, filename = "unknown" }: Object,
-  code: string,
-) {
-  try {
-    const results = [];
-    for (const plugins of pluginPasses) {
-      for (const plugin of plugins) {
-        const { parserOverride } = plugin;
-        if (parserOverride) {
-          const ast = parserOverride(code, parserOpts, parse);
-
-          if (ast !== undefined) results.push(ast);
-        }
-      }
-    }
-
-    if (results.length === 0) {
-      return parse(code, parserOpts);
-    } else if (results.length === 1) {
-      if (typeof results[0].then === "function") {
-        throw new Error(
-          `You appear to be using an async parser plugin, ` +
-            `which your current version of Babel does not support. ` +
-            `If you're using a published plugin, you may need to upgrade ` +
-            `your @babel/core version.`,
-        );
-      }
-      return results[0];
-    }
-    throw new Error("More than one plugin attempted to override parsing.");
-  } catch (err) {
-    if (err.code === "BABEL_PARSER_SOURCETYPE_MODULE_REQUIRED") {
-      err.message +=
-        "\nConsider renaming the file to '.mjs', or setting sourceType:module " +
-        "or sourceType:unambiguous in your Babel config for this file.";
-      // err.code will be changed to BABEL_PARSE_ERROR later.
-    }
-
-    const { loc, missingPlugin } = err;
-    if (loc) {
-      const codeFrame = codeFrameColumns(
-        code,
-        {
-          start: {
-            line: loc.line,
-            column: loc.column + 1,
-          },
-        },
-        {
-          highlightCode,
-        },
-      );
-      if (missingPlugin) {
-        err.message =
-          `${filename}: ` +
-          generateMissingPluginMessage(missingPlugin[0], loc, codeFrame);
-      } else {
-        err.message = `${filename}: ${err.message}\n\n` + codeFrame;
-      }
-      err.code = "BABEL_PARSE_ERROR";
-    }
-    throw err;
-  }
-}
-
 // These regexps are copied from the convert-source-map package,
 // but without // or /* at the beginning of the comment.