Cleanup and define GeneratedRange

jridgewell · Jun 24, 2024 · 86b883c · 86b883c
1 parent b16650e
commit 86b883c
Show file tree

Hide file tree

Showing 3 changed files with 158 additions and 52 deletions.
diff --git a/src/scopes.ts b/src/scopes.ts
@@ -4,41 +4,73 @@ import {
   encodeInteger,
   hasMoreVlq,
   indexOf,
-  maybeWrite,
+  maybeFlush,
   posOut,
-  semicolon,
+  write,
   td,
+  resetPos,
 } from './vlq';
 
 type Line = number;
 type Column = number;
 type Kind = number;
 type Name = number;
 type Var = number;
-
-type OriginalScope =
-  | [Line, Column, Line, Column, Kind, Name]
-  | [Line, Column, Line, Column, Kind, Name, Var]
-  | [Line, Column, Line, Column, Kind, Name, Var, Var]
-  | [Line, Column, Line, Column, Kind, Name, Var, Var, Var]
-  | [Line, Column, Line, Column, Kind, Name, Var, Var, Var, Var]
-  | [Line, Column, Line, Column, Kind, Name, Var, Var, Var, Var, Var];
+type SourcesIndex = number;
+type ScopesIndex = number;
+
+export type OriginalScope =
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: Kind;
+      length: 5;
+    }
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: Kind;
+      5: Name;
+      length: 6;
+    }
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: Kind;
+      vars: Var[];
+      length: 5;
+    }
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: Kind;
+      5: Name;
+      vars: Var[];
+      length: 6;
+    };
 
 const NO_NAME = -1;
+// const NO_SCOPE = -1;
 
 export function decodeOriginalScopes(input: string): OriginalScope[] {
   let line = 0;
-  let column = 0;
   let namesIndex = 0;
-  let varsIndex = 0;
   const scopes: OriginalScope[] = [];
   const stack: OriginalScope[] = [];
 
   for (let i = 0; i < input.length; i = posOut + 1) {
     line = decodeInteger(input, i, line);
-    column = decodeInteger(input, posOut, column);
+    const column = decodeInteger(input, posOut, 0);
 
-    if (!hasMoreVlq(input, posOut, length)) {
+    if (!hasMoreVlq(input, posOut, input.length)) {
       const last = stack.pop()!;
       last[2] = line;
       last[3] = column;
@@ -48,13 +80,19 @@ export function decodeOriginalScopes(input: string): OriginalScope[] {
     const kind = decodeInteger(input, posOut, 0);
     const fields = decodeInteger(input, posOut, 0);
     const name = fields & 0b1 ? decodeInteger(input, posOut, namesIndex) : NO_NAME;
-    const scope: OriginalScope = [line, column, 0, 0, kind, name];
+    const scope: OriginalScope =
+      name === NO_NAME ? [line, column, 0, 0, kind] : [line, column, 0, 0, kind, name];
+    scopes.push(scope);
     stack.push(scope);
 
     const index = indexOf(input, ',', posOut);
-    while (posOut < index) {
-      varsIndex = decodeInteger(input, posOut, varsIndex);
-      scope.push(varsIndex);
+    if (posOut < index) {
+      const vars: Var[] = [];
+      (scope as any).vars = vars;
+      while (posOut < index) {
+        const varsIndex = decodeInteger(input, posOut, 0);
+        vars.push(varsIndex);
+      }
     }
   }
 
@@ -69,49 +107,108 @@ export function encodeOriginalScopes(scopes: OriginalScope[]): string {
   const subLength = bufLength - (7 * 6 + 1);
   const buf = new Uint8Array(bufLength);
   const sub = buf.subarray(0, subLength);
-  let pos = 0;
+  resetPos();
 
-  const endStack: number[] = [0, 0];
-  let { 2: lastEndLine, 3: lastEndColumn } = scopes[scopes.length - 1];
+  const endStack: number[] = [];
+  let lastEndLine = scopes[0][2] + 1;
+  let lastEndColumn = scopes[0][3];
   let line = 0;
-  let column = 0;
   let namesIndex = 0;
-  let varsIndex = 0;
 
-  for (let i = 0; i < scopes.length; i++, pos = posOut) {
+  for (let i = 0; i < scopes.length; i++) {
     const scope = scopes[i];
-    const { 0: startLine, 1: startColumn, 2: endLine, 3: endColumn, 4: name } = scope;
+    const { 0: startLine, 1: startColumn, 2: endLine, 3: endColumn, 4: kind } = scope;
+    const name = scope.length === 6 ? scope[5] : NO_NAME;
+    const vars = 'vars' in scope ? scope.vars! : [];
 
-    out = maybeWrite(out, buf, pos, buf, bufLength);
-    pos = posOut;
-    if (i > 0) buf[pos++] = semicolon;
+    out = maybeFlush(out, buf, posOut, buf, bufLength);
+    if (i > 0) write(buf, posOut, comma);
 
     while (startLine > lastEndLine || (startLine === lastEndLine && startColumn >= lastEndColumn)) {
-      out = maybeWrite(out, sub, pos, buf, subLength);
+      out = maybeFlush(out, sub, posOut, buf, subLength);
 
       line = encodeInteger(buf, posOut, lastEndLine, line);
-      column = encodeInteger(buf, posOut, lastEndColumn, column);
-      pos = posOut;
-      buf[pos++] = comma;
+      encodeInteger(buf, posOut, lastEndColumn, 0);
+      write(buf, posOut, comma);
 
       lastEndColumn = endStack.pop()!;
       lastEndLine = endStack.pop()!;
     }
 
-    line = encodeInteger(buf, pos, startLine, line);
-    column = encodeInteger(buf, posOut, startColumn, column);
-    endStack.push(endLine);
-    endStack.push(endColumn);
+    line = encodeInteger(buf, posOut, startLine, line);
+    encodeInteger(buf, posOut, startColumn, 0);
+    endStack.push(lastEndLine);
+    endStack.push(lastEndColumn);
     lastEndLine = endLine;
     lastEndColumn = endColumn;
 
+    encodeInteger(buf, posOut, kind, 0);
     encodeInteger(buf, posOut, name === NO_NAME ? 0 : 1, 0);
     if (name !== NO_NAME) namesIndex = encodeInteger(buf, posOut, name, namesIndex);
 
-    for (let j = 5; j < scope.length; j++) {
-      out = maybeWrite(out, sub, pos, buf, subLength);
-      varsIndex = encodeInteger(buf, posOut, scope[j], varsIndex);
+    for (const v of vars) {
+      out = maybeFlush(out, sub, posOut, buf, subLength);
+      encodeInteger(buf, posOut, v, 0);
     }
   }
-  while (endStack.length > 0) {}
+  while (endStack.length > 0) {
+    out = maybeFlush(out, sub, posOut, buf, subLength);
+
+    write(buf, posOut, comma);
+    line = encodeInteger(buf, posOut, lastEndLine, line);
+    encodeInteger(buf, posOut, lastEndColumn, 0);
+
+    lastEndColumn = endStack.pop()!;
+    lastEndLine = endStack.pop()!;
+  }
+
+  return out + td.decode(buf.subarray(0, posOut));
+}
+
+export type GeneratedRange =
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: SourcesIndex;
+      5: ScopesIndex;
+    }
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: SourcesIndex;
+      5: ScopesIndex;
+      callsite: CallSite;
+    }
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: SourcesIndex;
+      5: ScopesIndex;
+      bindings: ExpressionBinding[];
+    }
+  | {
+      0: Line;
+      1: Column;
+      2: Line;
+      3: Column;
+      4: SourcesIndex;
+      5: ScopesIndex;
+      callsite: CallSite;
+      bindings: ExpressionBinding[];
+    };
+export type CallSite = [SourcesIndex, Line, Column];
+export type ExpressionBinding = [Name] | [Name, Line, Column];
+
+export function decodeGeneratedRanges(input: string): GeneratedRange[] {
+  return [];
+}
+
+export function encodeGeneratedRanges(ranges: GeneratedRange[]): string {
+  return '';
 }
diff --git a/src/sourcemap-codec.ts b/src/sourcemap-codec.ts
@@ -7,7 +7,9 @@ import {
   posOut,
   indexOf,
   td,
-  maybeWrite,
+  maybeFlush,
+  write,
+  resetPos,
 } from './vlq';
 // export { decodeOriginalScopes } from './scopes';
 
@@ -84,7 +86,7 @@ export function encode(decoded: Readonly<SourceMapMappings>): string {
   const subLength = bufLength - (7 * 5 + 1);
   const buf = new Uint8Array(bufLength);
   const sub = buf.subarray(0, subLength);
-  let pos = 0;
+  resetPos();
   let out = '';
   let genColumn = 0;
   let sourcesIndex = 0;
@@ -94,21 +96,19 @@ export function encode(decoded: Readonly<SourceMapMappings>): string {
 
   for (let i = 0; i < decoded.length; i++) {
     const line = decoded[i];
-    out = maybeWrite(out, buf, pos, buf, bufLength);
-    pos = posOut;
-    if (i > 0) buf[pos++] = semicolon;
+    out = maybeFlush(out, buf, posOut, buf, bufLength);
+    if (i > 0) write(buf, posOut, semicolon);
 
     if (line.length === 0) continue;
 
     genColumn = 0;
 
-    for (let j = 0; j < line.length; j++, pos = posOut) {
+    for (let j = 0; j < line.length; j++) {
       const segment = line[j];
-      out = maybeWrite(out, sub, pos, buf, subLength);
-      pos = posOut;
-      if (j > 0) buf[pos++] = comma;
+      out = maybeFlush(out, sub, posOut, buf, subLength);
+      if (j > 0) write(buf, posOut, comma);
 
-      genColumn = encodeInteger(buf, pos, segment[0], genColumn);
+      genColumn = encodeInteger(buf, posOut, segment[0], genColumn);
 
       if (segment.length === 1) continue;
       sourcesIndex = encodeInteger(buf, posOut, segment[1], sourcesIndex);
@@ -120,5 +120,5 @@ export function encode(decoded: Readonly<SourceMapMappings>): string {
     }
   }
 
-  return out + td.decode(buf.subarray(0, pos));
+  return out + td.decode(buf.subarray(0, posOut));
 }
diff --git a/src/vlq.ts b/src/vlq.ts
@@ -22,6 +22,10 @@ export function indexOf(mappings: string, char: string, index: number): number {
 }
 
 export let posOut = 0;
+export function resetPos() {
+  posOut = 0;
+}
+
 export function decodeInteger(mappings: string, pos: number, relative: number): number {
   let value = 0;
   let shift = 0;
@@ -60,7 +64,7 @@ export function encodeInteger(buf: Uint8Array, pos: number, num: number, relativ
   return num;
 }
 
-export function maybeWrite(
+export function maybeFlush(
   build: string,
   buf: Uint8Array,
   pos: number,
@@ -77,6 +81,11 @@ export function maybeWrite(
   return build + out;
 }
 
+export function write(buf: Uint8Array, pos: number, value: number) {
+  buf[pos] = value;
+  posOut = pos + 1;
+}
+
 // Provide a fallback for older environments.
 export const td =
   typeof TextDecoder !== 'undefined'