mutate() — react Function Reference

Architecture documentation for the mutate() function in InferMutationAliasingRanges.ts from the react codebase.

Function typescript BabelCompiler Validation calls 2 called by 1

Entity Profile

BabelCompiler→ Validation→ mutate() — react Function Reference

Dependency Diagram

graph TD
  cd8871a0_00ab_a3ba_98a3_61b6b75d973c["mutate()"]
  78bdc9d3_b80e_c93f_98e8_83b50c1b2b77["AliasingState"]
  cd8871a0_00ab_a3ba_98a3_61b6b75d973c -->|defined in| 78bdc9d3_b80e_c93f_98e8_83b50c1b2b77
  f3815d1a_36a1_3e3d_92f2_dbbe88f01fe3["inferMutationAliasingRanges()"]
  f3815d1a_36a1_3e3d_92f2_dbbe88f01fe3 -->|calls| cd8871a0_00ab_a3ba_98a3_61b6b75d973c
  d0270ab6_a621_bd55_a1b9_a5cad8b406b2["makeInstructionId()"]
  cd8871a0_00ab_a3ba_98a3_61b6b75d973c -->|calls| d0270ab6_a621_bd55_a1b9_a5cad8b406b2
  f54dd966_4662_1205_ce47_174c3758a7ff["appendFunctionErrors()"]
  cd8871a0_00ab_a3ba_98a3_61b6b75d973c -->|calls| f54dd966_4662_1205_ce47_174c3758a7ff
  style cd8871a0_00ab_a3ba_98a3_61b6b75d973c fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingRanges.ts lines 700–838

  mutate(
    index: number,
    start: Identifier,
    // Null is used for simulated mutations
    end: InstructionId | null,
    transitive: boolean,
    startKind: MutationKind,
    loc: SourceLocation,
    reason: MutationReason | null,
    errors: CompilerError,
  ): void {
    const seen = new Map<Identifier, MutationKind>();
    const queue: Array<{
      place: Identifier;
      transitive: boolean;
      direction: 'backwards' | 'forwards';
      kind: MutationKind;
    }> = [{place: start, transitive, direction: 'backwards', kind: startKind}];
    while (queue.length !== 0) {
      const {place: current, transitive, direction, kind} = queue.pop()!;
      const previousKind = seen.get(current);
      if (previousKind != null && previousKind >= kind) {
        continue;
      }
      seen.set(current, kind);
      const node = this.nodes.get(current);
      if (node == null) {
        continue;
      }
      node.mutationReason ??= reason;
      node.lastMutated = Math.max(node.lastMutated, index);
      if (end != null) {
        node.id.mutableRange.end = makeInstructionId(
          Math.max(node.id.mutableRange.end, end),
        );
      }
      if (
        node.value.kind === 'Function' &&
        node.transitive == null &&
        node.local == null
      ) {
        appendFunctionErrors(errors, node.value.function);
      }
      if (transitive) {
        if (node.transitive == null || node.transitive.kind < kind) {
          node.transitive = {kind, loc};
        }
      } else {
        if (node.local == null || node.local.kind < kind) {
          node.local = {kind, loc};
        }
      }
      /**
       * all mutations affect "forward" edges by the rules:
       * - Capture a -> b, mutate(a) => mutate(b)
       * - Alias a -> b, mutate(a) => mutate(b)
       */
      for (const edge of node.edges) {
        if (edge.index >= index) {
          break;
        }
        queue.push({
          place: edge.node,
          transitive,
          direction: 'forwards',
          // Traversing a maybeAlias edge always downgrades to conditional mutation
          kind: edge.kind === 'maybeAlias' ? MutationKind.Conditional : kind,
        });
      }
      for (const [alias, when] of node.createdFrom) {
        if (when >= index) {
          continue;
        }
        queue.push({
          place: alias,
          transitive: true,
          direction: 'backwards',
          kind,
        });
      }
      if (direction === 'backwards' || node.value.kind !== 'Phi') {