Use maybeAddMapping to add sourcemap markings (#14510)

packages/babel-core/test/fixtures/transformation/source-maps/input-source-map-multiple-output-sources-complete-replace/source-map.json

@@ -1,13 +1,15 @@
 {
-  "mappings": "AAAC;ACAD,K",
+  "version": 3,
+  "mappings": "AAAC,KCAD;ACAA,K",
   "names": [],
   "sources": [
     "bar.js",
+    "input.tsx",
     "baz.js"
   ],
   "sourcesContent": [
     "<bar />",
+    "foo(1);\nfunction foo(bar: number): never {\n    throw new Error('Intentional.');\n}",
     "baz();"
-  ],
-  "version": 3
-}
+  ]
+}

packages/babel-core/test/fixtures/transformation/source-maps/input-source-map-multiple-output-sources/source-map.json

@@ -1,6 +1,6 @@
 {
   "version": 3,
-  "mappings": "AAAC;;ACCD,SAASA,GAAT,CAAaC,GAAb,EAAwB;EACpB,MAAM,IAAIC,KAAJ,CAAU,cAAV,CAAN;AACH",
+  "mappings": "AAAC,KCAD;;AACA,SAASA,GAAT,CAAaC,GAAb,EAAwB;EACpB,MAAM,IAAIC,KAAJ,CAAU,cAAV,CAAN;AACH",
   "names": [
     "foo",
     "bar",

packages/babel-core/test/fixtures/transformation/source-maps/input-source-map-sources-complete-replace/source-map.json

@@ -1,7 +1,13 @@
 {
-  "mappings": "AAAC",
+  "version": 3,
+  "mappings": "AAAC,KCAD",
   "names": [],
-  "sources": ["test.js"],
-  "sourcesContent": ["<bar />"],
-  "version": 3
-}
+  "sources": [
+    "test.js",
+    "input.tsx"
+  ],
+  "sourcesContent": [
+    "<bar />",
+    "foo(1);\nfunction foo(bar: number): never {\n    throw new Error('Intentional.');\n}"
+  ]
+}

packages/babel-generator/package.json

@@ -20,7 +20,7 @@
   ],
   "dependencies": {
     "@babel/types": "workspace:^",
-    "@jridgewell/gen-mapping": "^0.1.0",
+    "@jridgewell/gen-mapping": "^0.3.0",
     "jsesc": "condition: BABEL_8_BREAKING ? ^3.0.2 : ^2.5.1"
   },
   "devDependencies": {

packages/babel-generator/src/buffer.ts

@@ -17,7 +17,6 @@ type SourcePos = {
   line: number | undefined;
   column: number | undefined;
   filename: string | undefined;
-  force: boolean;
 };
 
 function SourcePos(): SourcePos {
@@ -26,7 +25,6 @@ function SourcePos(): SourcePos {
     line: undefined,
     column: undefined,
     filename: undefined,
-    force: false,
   };
 }
 
@@ -88,9 +86,8 @@ export default class Buffer {
 
   append(str: string): void {
     this._flush();
-    const { line, column, filename, identifierName, force } =
-      this._sourcePosition;
-    this._append(str, line, column, identifierName, filename, force);
+    const { line, column, filename, identifierName } = this._sourcePosition;
+    this._append(str, line, column, identifierName, filename);
   }
 
   /**
@@ -104,23 +101,15 @@ export default class Buffer {
       }
     }
 
-    const { line, column, filename, identifierName, force } =
-      this._sourcePosition;
-    this._queue.unshift([str, line, column, identifierName, filename, force]);
+    const { line, column, filename, identifierName } = this._sourcePosition;
+    this._queue.unshift([str, line, column, identifierName, filename]);
   }
 
   /**
    * Same as queue, but this indentation will never have a sourcmap marker.
    */
   queueIndentation(str: string): void {
-    this._queue.unshift([
-      str,
-      undefined,
-      undefined,
-      undefined,
-      undefined,
-      false,
-    ]);
+    this._queue.unshift([str, undefined, undefined, undefined, undefined]);
   }
 
   _flush(): void {
@@ -132,11 +121,10 @@ export default class Buffer {
 
   _append(
     str: string,
-    line: number,
-    column: number,
+    line: number | undefined,
+    column: number | undefined,
     identifierName: string | undefined,
     filename: string | undefined,
-    force: boolean,
   ): void {
     this._buf += str;
     this._last = str.charCodeAt(str.length - 1);
@@ -151,7 +139,7 @@ export default class Buffer {
     // If the string starts with a newline char, then adding a mark is redundant.
     // This catches both "no newlines" and "newline after several chars".
     if (i !== 0) {
-      this._mark(line, column, identifierName, filename, force);
+      this._mark(line, column, identifierName, filename);
     }
 
     // Now, find each reamining newline char in the string.
@@ -163,28 +151,20 @@ export default class Buffer {
       // We mark the start of each line, which happens directly after this newline char
       // unless this is the last char.
       if (last < str.length) {
-        this._mark(++line, 0, identifierName, filename, force);
+        this._mark(++line, 0, identifierName, filename);
       }
       i = str.indexOf("\n", last);
     }
     this._position.column += str.length - last;
   }
 
   _mark(
-    line: number,
-    column: number,
-    identifierName?: string | null,
-    filename?: string | null,
-    force?: boolean,
+    line: number | undefined,
+    column: number | undefined,
+    identifierName: string | undefined,
+    filename: string | undefined,
   ): void {
-    this._map?.mark(
-      this._position,
-      line,
-      column,
-      identifierName,
-      filename,
-      force,
-    );
+    this._map?.mark(this._position, line, column, identifierName, filename);
   }
 
   removeTrailingNewline(): void {
@@ -262,11 +242,7 @@ export default class Buffer {
    * over "();", where previously it would have been a single mapping.
    */
   exactSource(loc: any, cb: () => void) {
-    // In cases where parent expressions start at the same locations as the
-    // identifier itself, the current active location could already be the
-    // start of this range. We use 'force' here to explicitly start a new
-    // mapping range for this new token.
-    this.source("start", loc, true /* force */);
+    this.source("start", loc);
 
     cb();
 
@@ -286,12 +262,12 @@ export default class Buffer {
    * will be given this position in the sourcemap.
    */
 
-  source(prop: string, loc: t.SourceLocation, force?: boolean): void {
+  source(prop: string, loc: t.SourceLocation): void {
     if (prop && !loc) return;
 
     // Since this is called extremely often, we re-use the same _sourcePosition
     // object for the whole lifetime of the buffer.
-    this._normalizePosition(prop, loc, this._sourcePosition, force);
+    this._normalizePosition(prop, loc, this._sourcePosition);
   }
 
   /**
@@ -314,23 +290,16 @@ export default class Buffer {
     cb();
 
     if (
-      // If the current active position is forced, we only want to reactivate
-      // the old position if it is different from the newest position.
-      (!this._sourcePosition.force ||
-        this._sourcePosition.line !== originalLine ||
-        this._sourcePosition.column !== originalColumn ||
-        this._sourcePosition.filename !== originalFilename) &&
       // Verify if reactivating this specific position has been disallowed.
-      (!this._disallowedPop ||
-        this._disallowedPop.line !== originalLine ||
-        this._disallowedPop.column !== originalColumn ||
-        this._disallowedPop.filename !== originalFilename)
+      !this._disallowedPop ||
+      this._disallowedPop.line !== originalLine ||
+      this._disallowedPop.column !== originalColumn ||
+      this._disallowedPop.filename !== originalFilename
     ) {
       this._sourcePosition.line = originalLine;
       this._sourcePosition.column = originalColumn;
       this._sourcePosition.filename = originalFilename;
       this._sourcePosition.identifierName = originalIdentifierName;
-      this._sourcePosition.force = false;
       this._disallowedPop = null;
     }
   }
@@ -343,42 +312,22 @@ export default class Buffer {
   _disallowPop(prop: string, loc: t.SourceLocation) {
     if (prop && !loc) return;
 
-    this._disallowedPop = this._normalizePosition(
-      prop,
-      loc,
-      SourcePos(),
-      false,
-    );
+    this._disallowedPop = this._normalizePosition(prop, loc, SourcePos());
   }
 
   _normalizePosition(
     prop: string,
     loc: Loc | undefined | null,
     targetObj: SourcePos,
-    force: boolean,
   ) {
     const pos = loc ? loc[prop] : null;
 
-    const origLine = targetObj.line;
-    const origColumn = targetObj.column;
-    const origFilename = targetObj.filename;
-
     targetObj.identifierName =
-      (prop === "start" && loc?.identifierName) || null;
+      (prop === "start" && loc?.identifierName) || undefined;
     targetObj.line = pos?.line;
     targetObj.column = pos?.column;
     targetObj.filename = loc?.filename;
 
-    // We want to skip reassigning `force` if we're re-setting the same position.
-    if (
-      force ||
-      targetObj.line !== origLine ||
-      targetObj.column !== origColumn ||
-      targetObj.filename !== origFilename
-    ) {
-      targetObj.force = force;
-    }
-
     return targetObj;
   }
 

packages/babel-generator/src/source-map.ts

@@ -1,10 +1,10 @@
 import {
   GenMapping,
-  addMapping,
+  maybeAddMapping,
   setSourceContent,
   allMappings,
-  encodedMap,
-  decodedMap,
+  toEncodedMap,
+  toDecodedMap,
 } from "@jridgewell/gen-mapping";
 
 import type {
@@ -55,11 +55,11 @@ export default class SourceMap {
    * Get the sourcemap.
    */
   get(): EncodedSourceMap {
-    return encodedMap(this._map);
+    return toEncodedMap(this._map);
   }
 
   getDecoded(): DecodedSourceMap {
-    return decodedMap(this._map);
+    return toDecodedMap(this._map);
   }
 
   getRawMappings(): Mapping[] {
@@ -77,30 +77,10 @@ export default class SourceMap {
     column: number,
     identifierName?: string | null,
     filename?: string | null,
-    force?: boolean,
   ) {
-    const generatedLine = generated.line;
-
-    // Adding an empty mapping at the start of a generated line just clutters the map.
-    if (this._lastGenLine !== generatedLine && line == null) return;
-
-    // If this mapping points to the same source location as the last one, we can ignore it since
-    // the previous one covers it.
-    if (
-      !force &&
-      this._lastGenLine === generatedLine &&
-      this._lastSourceLine === line &&
-      this._lastSourceColumn === column
-    ) {
-      return;
-    }
-
     this._rawMappings = undefined;
-    this._lastGenLine = generatedLine;
-    this._lastSourceLine = line;
-    this._lastSourceColumn = column;
 
-    addMapping(this._map, {
+    maybeAddMapping(this._map, {
       name: identifierName,
       generated,
       source:

yarn.lock

@@ -456,7 +456,7 @@ __metadata:
     "@babel/helper-fixtures": "workspace:^"
     "@babel/parser": "workspace:^"
     "@babel/types": "workspace:^"
-    "@jridgewell/gen-mapping": ^0.1.0
+    "@jridgewell/gen-mapping": ^0.3.0
     "@jridgewell/trace-mapping": ^0.3.8
     "@types/jsesc": ^2.5.0
     charcodes: ^0.2.0
@@ -4070,13 +4070,14 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@jridgewell/gen-mapping@npm:^0.1.0":
-  version: 0.1.0
-  resolution: "@jridgewell/gen-mapping@npm:0.1.0"
+"@jridgewell/gen-mapping@npm:^0.3.0":
+  version: 0.3.0
+  resolution: "@jridgewell/gen-mapping@npm:0.3.0"
   dependencies:
-    "@jridgewell/set-array": 1.0.0
+    "@jridgewell/set-array": ^1.0.0
     "@jridgewell/sourcemap-codec": ^1.4.10
-  checksum: 8611de5acbea55fa84bcde0d6f803e006560f7a8ce618ba427e20a76913d18308fc14d5cfb324e30d0051556a96527fbc4e64cf65d68f121170776243387dcce
+    "@jridgewell/trace-mapping": ^0.3.9
+  checksum: ccc9b288d2bbf09d81a85cd07b0e0dd461f2a8d2fd0d46eefc1c04e994e9f95a51bb9e1c8718f4182e87a21c11d2f5ed687a789024cbd160c8e5421de8b011f6
   languageName: node
   linkType: hard
 
@@ -4087,10 +4088,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@jridgewell/set-array@npm:1.0.0":
-  version: 1.0.0
-  resolution: "@jridgewell/set-array@npm:1.0.0"
-  checksum: 35dd48a205099839fa8b9e9b7138d382d1f33457404c4e96c95ad1cd9aea99904737b351d4dea8b21fa17b50fcd0dc2fdbf4c04fc4bcd3c1a42d079217261444
+"@jridgewell/set-array@npm:^1.0.0":
+  version: 1.1.0
+  resolution: "@jridgewell/set-array@npm:1.1.0"
+  checksum: 86ddd72ce7d2f7756dfb69804b35d0e760a85dcef30ed72e8610bf2c5e843f8878d977a0c77c4fdfa6a0e3d5b18e5bde4a1f1dd73fd2db06b200c998e9b5a6c5
   languageName: node
   linkType: hard
 
@@ -4101,13 +4102,13 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@jridgewell/trace-mapping@npm:^0.3.0, @jridgewell/trace-mapping@npm:^0.3.8":
-  version: 0.3.8
-  resolution: "@jridgewell/trace-mapping@npm:0.3.8"
+"@jridgewell/trace-mapping@npm:^0.3.0, @jridgewell/trace-mapping@npm:^0.3.8, @jridgewell/trace-mapping@npm:^0.3.9":
+  version: 0.3.9
+  resolution: "@jridgewell/trace-mapping@npm:0.3.9"
   dependencies:
     "@jridgewell/resolve-uri": ^3.0.3
     "@jridgewell/sourcemap-codec": ^1.4.10
-  checksum: 4b46f28c785133773de521677983186dfe7ed80872bee57b73624527e345954139ea45dfb7551a5f04de1773dc9501b896554a8f1c9e1c44ab2146a3c66b6fda
+  checksum: d89597752fd88d3f3480845691a05a44bd21faac18e2185b6f436c3b0fd0c5a859fbbd9aaa92050c4052caf325ad3e10e2e1d1b64327517471b7d51babc0ddef
   languageName: node
   linkType: hard