simplifyConditionals() — react Function Reference

Architecture documentation for the simplifyConditionals() function in minimize.ts from the react codebase.

Function typescript BabelCompiler Optimization calls 1

Entity Profile

BabelCompiler→ Optimization→ simplifyConditionals() — react Function Reference

Dependency Diagram

graph TD
  c981d44f_eaca_d663_3510_3c6d4f4c260b["simplifyConditionals()"]
  9c061da8_dbf8_4168_823d_991654a3c55d["minimize.ts"]
  c981d44f_eaca_d663_3510_3c6d4f4c260b -->|defined in| 9c061da8_dbf8_4168_823d_991654a3c55d
  7a9af496_ef6a_d9e8_8eaf_1f386f49e4b3["cloneAst()"]
  c981d44f_eaca_d663_3510_3c6d4f4c260b -->|calls| 7a9af496_ef6a_d9e8_8eaf_1f386f49e4b3
  style c981d44f_eaca_d663_3510_3c6d4f4c260b fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

compiler/packages/snap/src/minimize.ts lines 361–435

function* simplifyConditionals(ast: t.File): Generator<t.File> {
  // Count conditionals
  let condCount = 0;
  t.traverseFast(ast, node => {
    if (t.isConditionalExpression(node)) {
      condCount++;
    }
  });

  // Try replacing with test condition
  for (let targetIdx = 0; targetIdx < condCount; targetIdx++) {
    const cloned = cloneAst(ast);
    let modified = false;
    let idx = 0;

    traverse(cloned, {
      ConditionalExpression(path) {
        if (modified) return;
        if (idx === targetIdx) {
          path.replaceWith(path.node.test);
          modified = true;
        }
        idx++;
      },
    });

    if (modified) {
      yield cloned;
    }
  }

  // Try replacing with consequent
  for (let targetIdx = 0; targetIdx < condCount; targetIdx++) {
    const cloned = cloneAst(ast);
    let modified = false;
    let idx = 0;

    traverse(cloned, {
      ConditionalExpression(path) {
        if (modified) return;
        if (idx === targetIdx) {
          path.replaceWith(path.node.consequent);
          modified = true;
        }
        idx++;
      },
    });

    if (modified) {
      yield cloned;
    }
  }

  // Also try replacing with alternate
  for (let targetIdx = 0; targetIdx < condCount; targetIdx++) {
    const cloned = cloneAst(ast);
    let modified = false;
    let idx = 0;

    traverse(cloned, {
      ConditionalExpression(path) {
        if (modified) return;
        if (idx === targetIdx) {
          path.replaceWith(path.node.alternate);
          modified = true;
        }
        idx++;
      },
    });

    if (modified) {
      yield cloned;
    }
  }
}