union() — react Function Reference

Architecture documentation for the union() function in DisjointSet.ts from the react codebase.

Function typescript BabelCompiler Validation calls 2

Entity Profile

BabelCompiler→ Validation→ union() — react Function Reference

Dependency Diagram

graph TD
  a89a21a8_52fd_f4df_8805_31b9e3fb228e["union()"]
  1765a682_3028_4441_b26f_c712ca2597d5["DisjointSet"]
  a89a21a8_52fd_f4df_8805_31b9e3fb228e -->|defined in| 1765a682_3028_4441_b26f_c712ca2597d5
  74efde51_a311_d84c_0e23_ddafd072e338["find()"]
  a89a21a8_52fd_f4df_8805_31b9e3fb228e -->|calls| 74efde51_a311_d84c_0e23_ddafd072e338
  041ca752_10c1_3cda_1f5c_02f44a01310e["invariant()"]
  a89a21a8_52fd_f4df_8805_31b9e3fb228e -->|calls| 041ca752_10c1_3cda_1f5c_02f44a01310e
  style a89a21a8_52fd_f4df_8805_31b9e3fb228e fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

compiler/packages/babel-plugin-react-compiler/src/Utils/DisjointSet.ts lines 20–54

  union(items: Array<T>): void {
    const first = items.shift();
    CompilerError.invariant(first != null, {
      reason: 'Expected set to be non-empty',
      loc: GeneratedSource,
    });
    /*
     * determine an arbitrary "root" for this set: if the first
     * item already has a root then use that, otherwise the first item
     * will be the new root.
     */
    let root = this.find(first);
    if (root == null) {
      root = first;
      this.#entries.set(first, first);
    }
    // update remaining items (which may already be part of other sets)
    for (const item of items) {
      let itemParent = this.#entries.get(item);
      if (itemParent == null) {
        // new item, no existing set to update
        this.#entries.set(item, root);
        continue;
      } else if (itemParent === root) {
        continue;
      } else {
        let current = item;
        while (itemParent !== root) {
          this.#entries.set(current, root);
          current = itemParent;
          itemParent = this.#entries.get(current)!;
        }
      }
    }
  }