oxc-project__oxc/apps/oxlint/test/fixtures/fixes/plugin.ts

import { sep as pathSep } from "node:path";
import assert from "node:assert";

import type { Diagnostic, Node, Plugin, Rule } from "#oxlint/plugins";

const U32_MAX_PLUS_ONE = 2 ** 32;

const rule: Rule = {
  meta: {
    fixable: "code",
  },
  create(context) {
    // Check file has not been formatted by accident.
    // We want the fixture files not to have trailing whitespace to check fixes at very end of file.
    const sourceText = context.sourceCode.text;
    assert(!sourceText.endsWith("\n"), "Fixture file has been formatted");

    const path = context.filename;
    const filename = path.slice(path.lastIndexOf(pathSep) + 1);

    let debuggerCount = 0;

    return {
      Program(node) {
        // Remove BOM in `bom_remove.js` and `bom_remove2.js`.
        // ESLint's `unicode-bom` rule returns fixes with `range: [-1, 0]` to remove BOM.
        // Check behavior is correct for both `fix` returning a single fix and returning multiple fixes.
        if (filename === "bom_remove.js") {
          context.report({
            message: "Remove BOM",
            node,
            fix(fixer) {
              return fixer.removeRange([-1, 0]);
            },
          });
        } else if (filename === "bom_remove2.js") {
          context.report({
            message: "Remove BOM multiple",
            node,
            fix(fixer) {
              return [fixer.removeRange([0, 0]), fixer.removeRange([-1, 0])];
            },
          });
        }
      },

      DebuggerStatement(node) {
        debuggerCount++;

        let thisIsReport;
        const report: Diagnostic = {
          message: "Remove debugger statement",
          node,
          fix(fixer) {
            thisIsReport = this === report;
            if (debuggerCount === 1) return fixer.remove(node);
            return fixer.removeRange([node.start, node.end]);
          },
        };
        context.report(report);

        if (!thisIsReport) {
          context.report({ message: `this in fix function is not report object`, node });
        }
      },

      Identifier(node) {
        switch (node.name) {
          case "a":
            return context.report({
              message: 'Replace "a" with "daddy"',
              node,
              fix(fixer) {
                return fixer.replaceText(node, "daddy");
              },
            });

          case "b":
            return context.report({
              message: 'Replace "b" with "abacus"',
              node,
              fix(fixer) {
                return fixer.replaceTextRange([node.start, node.end], "abacus");
              },
            });

          case "c":
            return context.report({
              message: 'Prefix "c" with "magi"',
              node,
              fix(fixer) {
                return fixer.insertTextBefore(node, "magi");
              },
            });

          case "d":
            return context.report({
              message: 'Prefix "d" with "damne"',
              node,
              fix(fixer) {
                return fixer.insertTextBeforeRange([node.start, node.end], "damne");
              },
            });

          case "e":
            return context.report({
              message: 'Postfix "e" with "lephant"',
              node,
              fix(fixer) {
                return fixer.insertTextAfter(node, "lephant");
              },
            });

          case "f":
            return context.report({
              message: 'Postfix "f" with "eck"',
              node,
              fix(fixer) {
                return fixer.insertTextAfterRange([node.start, node.end], "eck");
              },
            });

          case "g":
            return context.report({
              message: 'Replace "g" with "rage"',
              node,
              fix(fixer) {
                // Add text before and after the node only, to test combining fixes that include original source.
                // Fixes can be in any order.
                return [
                  // Test that any object with `range` property works
                  fixer.insertTextAfter({ range: [node.start, node.end] }, "e"),
                  fixer.insertTextBefore(node, "ra"),
                ];
              },
            });

          case "h":
            return context.report({
              message: 'Replace "h" with "dangermouse"',
              node,
              fix(fixer) {
                // Fixes can be in any order
                const { range } = node;
                return [
                  fixer.replaceTextRange(range, "er"),
                  fixer.insertTextAfterRange(range, "mouse"),
                  fixer.insertTextBeforeRange(range, "dang"),
                ];
              },
            });

          case "i":
            return context.report({
              message: 'Replace "i" with "granular"',
              node,
              // `fix` can be a generator function
              *fix(fixer) {
                yield fixer.insertTextBefore(node, "gra");
                yield fixer.replaceText(node, "nu");
                // Test that any object with `range` property works
                yield fixer.insertTextAfter({ range: [node.start, node.end] } as Node, "lar");
              },
            });

          case "j":
            return context.report({
              message: 'Replace "j" with "cowabunga"',
              node,
              // `fix` can be a generator function
              *fix(fixer) {
                // Fixes can be in any order
                const { range } = node;
                yield fixer.insertTextAfterRange(range, "bunga");
                yield fixer.replaceTextRange(range, "a");
                yield fixer.insertTextBeforeRange(range, "cow");
              },
            });

          // Test behavior when `fix` returns a fix with illegal range.
          // Check behavior is correct for both `fix` returning a single fix and returning multiple fixes.
          case "x":
            switch (filename) {
              case "range_start_after_end.js":
                context.report({
                  message: "start after end",
                  node,
                  fix(fixer) {
                    return fixer.removeRange([3, 2]);
                  },
                });
                context.report({
                  message: "start after end multiple",
                  node,
                  fix(fixer) {
                    return [fixer.removeRange([0, 0]), fixer.removeRange([3, 2])];
                  },
                });
                break;

              case "range_end_out_of_bounds.js":
                context.report({
                  message: "end out of bounds",
                  node,
                  fix(fixer) {
                    return fixer.removeRange([0, sourceText.length + 1]);
                  },
                });
                context.report({
                  message: "end out of bounds multiple",
                  node,
                  fix(fixer) {
                    return [
                      fixer.removeRange([0, 0]),
                      fixer.removeRange([0, sourceText.length + 1]),
                    ];
                  },
                });
                break;

              case "range_start_too_large.js":
                context.report({
                  message: "start too large",
                  node,
                  fix(fixer) {
                    return fixer.removeRange([U32_MAX_PLUS_ONE, 0]);
                  },
                });
                context.report({
                  message: "start too large multiple",
                  node,
                  fix(fixer) {
                    return [fixer.removeRange([0, 0]), fixer.removeRange([U32_MAX_PLUS_ONE, 0])];
                  },
                });
                break;

              case "range_end_too_large.js":
                context.report({
                  message: "end too large",
                  node,
                  fix(fixer) {
                    return fixer.removeRange([0, U32_MAX_PLUS_ONE]);
                  },
                });
                context.report({
                  message: "end too large multiple",
                  node,
                  fix(fixer) {
                    return [fixer.removeRange([0, 0]), fixer.removeRange([0, U32_MAX_PLUS_ONE])];
                  },
                });
                break;

              case "range_start_negative.js":
                context.report({
                  message: "start negative",
                  node,
                  fix(fixer) {
                    return fixer.removeRange([-10, 0]);
                  },
                });
                context.report({
                  message: "start negative multiple",
                  node,
                  fix(fixer) {
                    return [fixer.removeRange([0, 0]), fixer.removeRange([-10, 0])];
                  },
                });
                break;

              case "range_end_negative.js":
                context.report({
                  message: "end negative",
                  node,
                  fix(fixer) {
                    return fixer.removeRange([0, -10]);
                  },
                });
                context.report({
                  message: "end negative multiple",
                  node,
                  fix(fixer) {
                    return [fixer.removeRange([0, 0]), fixer.removeRange([0, -10])];
                  },
                });
                break;
            }
        }
      },
    };
  },
};

const plugin: Plugin = {
  meta: {
    name: "fixes-plugin",
  },
  rules: {
    fixes: rule,
  },
};

export default plugin;