index.js

import Printer from "../lib/printer";
import generate, { CodeGenerator } from "../lib";
import { parse } from "@babel/parser";
import * as t from "@babel/types";
import fs from "fs";
import path from "path";
import fixtures from "@babel/helper-fixtures";

describe("generation", function() {
  it("completeness", function() {
    Object.keys(t.VISITOR_KEYS).forEach(function(type) {
      expect(Printer.prototype[type]).toBeTruthy();
    });

    Object.keys(Printer.prototype).forEach(function(type) {
      if (!/[A-Z]/.test(type[0])) return;
      expect(t.VISITOR_KEYS[type]).toBeTruthy();
    });
  });

  it("multiple sources", function() {
    const sources = {
      "a.js": "function hi (msg) { console.log(msg); }\n",
      "b.js": "hi('hello');\n",
    };
    const parsed = Object.keys(sources).reduce(function(_parsed, filename) {
      _parsed[filename] = parse(sources[filename], {
        sourceFilename: filename,
      });
      return _parsed;
    }, {});

    const combinedAst = {
      type: "File",
      program: {
        type: "Program",
        sourceType: "module",
        body: [].concat(
          parsed["a.js"].program.body,
          parsed["b.js"].program.body,
        ),
      },
    };

    const generated = generate(combinedAst, { sourceMaps: true }, sources);

    expect(generated.map).toEqual(
      {
        version: 3,
        sources: ["a.js", "b.js"],
        mappings:
          // eslint-disable-next-line max-len
          "AAAA,SAASA,EAAT,CAAaC,GAAb,EAAkB;AAAEC,EAAAA,OAAO,CAACC,GAAR,CAAYF,GAAZ;AAAmB;;ACAvCD,EAAE,CAAC,OAAD,CAAF",
        names: ["hi", "msg", "console", "log"],
        sourcesContent: [
          "function hi (msg) { console.log(msg); }\n",
          "hi('hello');\n",
        ],
      },
      "sourcemap was incorrectly generated",
    );

    expect(generated.rawMappings).toEqual(
      [
        {
          name: undefined,
          generated: { line: 1, column: 0 },
          source: "a.js",
          original: { line: 1, column: 0 },
        },
        {
          name: "hi",
          generated: { line: 1, column: 9 },
          source: "a.js",
          original: { line: 1, column: 9 },
        },
        {
          name: undefined,
          generated: { line: 1, column: 11 },
          source: "a.js",
          original: { line: 1, column: 0 },
        },
        {
          name: "msg",
          generated: { line: 1, column: 12 },
          source: "a.js",
          original: { line: 1, column: 13 },
        },
        {
          name: undefined,
          generated: { line: 1, column: 15 },
          source: "a.js",
          original: { line: 1, column: 0 },
        },
        {
          name: undefined,
          generated: { line: 1, column: 17 },
          source: "a.js",
          original: { line: 1, column: 18 },
        },
        {
          name: "console",
          generated: { line: 2, column: 0 },
          source: "a.js",
          original: { line: 1, column: 20 },
        },
        {
          name: "console",
          generated: { line: 2, column: 2 },
          source: "a.js",
          original: { line: 1, column: 20 },
        },
        {
          name: undefined,
          generated: { line: 2, column: 9 },
          source: "a.js",
          original: { line: 1, column: 27 },
        },
        {
          name: "log",
          generated: { line: 2, column: 10 },
          source: "a.js",
          original: { line: 1, column: 28 },
        },
        {
          name: undefined,
          generated: { line: 2, column: 13 },
          source: "a.js",
          original: { line: 1, column: 20 },
        },
        {
          name: "msg",
          generated: { line: 2, column: 14 },
          source: "a.js",
          original: { line: 1, column: 32 },
        },
        {
          name: undefined,
          generated: { line: 2, column: 17 },
          source: "a.js",
          original: { line: 1, column: 20 },
        },
        {
          name: undefined,
          generated: { line: 3, column: 0 },
          source: "a.js",
          original: { line: 1, column: 39 },
        },
        {
          name: "hi",
          generated: { line: 5, column: 0 },
          source: "b.js",
          original: { line: 1, column: 0 },
        },
        {
          name: undefined,
          generated: { line: 5, column: 2 },
          source: "b.js",
          original: { line: 1, column: 2 },
        },
        {
          name: undefined,
          generated: { line: 5, column: 3 },
          source: "b.js",
          original: { line: 1, column: 3 },
        },
        {
          name: undefined,
          generated: { line: 5, column: 10 },
          source: "b.js",
          original: { line: 1, column: 2 },
        },
        {
          name: undefined,
          generated: { line: 5, column: 11 },
          source: "b.js",
          original: { line: 1, column: 0 },
        },
      ],
      "raw mappings were incorrectly generated",
    );

    expect(generated.code).toBe(
      "function hi(msg) {\n  console.log(msg);\n}\n\nhi('hello');",
    );
  });

  it("identifierName", function() {
    const code = "function foo() { bar; }\n";

    const ast = parse(code, { filename: "inline" }).program;
    const fn = ast.body[0];

    const id = fn.id;
    id.name += "2";
    id.loc.identifierName = "foo";

    const id2 = fn.body.body[0].expression;
    id2.name += "2";
    id2.loc.identifierName = "bar";

    const generated = generate(
      ast,
      {
        filename: "inline",
        sourceFileName: "inline",
        sourceMaps: true,
      },
      code,
    );

    expect(generated.map).toEqual(
      {
        version: 3,
        sources: ["inline"],
        names: ["foo", "bar"],
        mappings: "AAAA,SAASA,IAAT,GAAe;AAAEC,EAAAA,IAAG;AAAG",
        sourcesContent: ["function foo() { bar; }\n"],
      },
      "sourcemap was incorrectly generated",
    );

    expect(generated.rawMappings).toEqual(
      [
        {
          name: undefined,
          generated: { line: 1, column: 0 },
          source: "inline",
          original: { line: 1, column: 0 },
        },
        {
          name: "foo",
          generated: { line: 1, column: 9 },
          source: "inline",
          original: { line: 1, column: 9 },
        },
        {
          name: undefined,
          generated: { line: 1, column: 13 },
          source: "inline",
          original: { line: 1, column: 0 },
        },
        {
          name: undefined,
          generated: { line: 1, column: 16 },
          source: "inline",
          original: { line: 1, column: 15 },
        },
        {
          name: "bar",
          generated: { line: 2, column: 0 },
          source: "inline",
          original: { line: 1, column: 17 },
        },
        {
          name: "bar",
          generated: { line: 2, column: 2 },
          source: "inline",
          original: { line: 1, column: 17 },
        },
        {
          name: undefined,
          generated: { line: 2, column: 6 },
          source: "inline",
          original: { line: 1, column: 20 },
        },
        {
          name: undefined,
          generated: { line: 3, column: 0 },
          source: "inline",
          original: { line: 1, column: 23 },
        },
      ],
      "raw mappings were incorrectly generated",
    );

    expect(generated.code).toBe("function foo2() {\n  bar2;\n}");
  });

  it("lazy source map generation", function() {
    const code = "function hi (msg) { console.log(msg); }\n";

    const ast = parse(code, { filename: "a.js" }).program;
    const generated = generate(ast, {
      sourceFileName: "a.js",
      sourceMaps: true,
    });

    expect(Array.isArray(generated.rawMappings)).toBe(true);

    expect(
      Object.getOwnPropertyDescriptor(generated, "map"),
    ).not.toHaveProperty("value");

    expect(generated).toHaveProperty("map");
    expect(typeof generated.map).toBe("object");
  });
});

describe("programmatic generation", function() {
  it("should add parenthesis when NullishCoalescing is used along with ||", function() {
    // https://github.com/babel/babel/issues/10260
    const nullishCoalesc = t.logicalExpression(
      "??",
      t.logicalExpression("||", t.identifier("a"), t.identifier("b")),
      t.identifier("c"),
    );
    const output = generate(nullishCoalesc).code;
    expect(output).toBe(`(a || b) ?? c`);
  });

  it("should add parenthesis when NullishCoalesing is used with &&", function() {
    const nullishCoalesc = t.logicalExpression(
      "??",
      t.identifier("a"),
      t.logicalExpression(
        "&&",
        t.identifier("b"),
        t.logicalExpression("&&", t.identifier("c"), t.identifier("d")),
      ),
    );
    const output = generate(nullishCoalesc).code;
    expect(output).toBe(`a ?? (b && c && d)`);
  });

  it("numeric member expression", function() {
    // Should not generate `0.foo`
    const mem = t.memberExpression(
      t.numericLiteral(60702),
      t.identifier("foo"),
    );
    new Function(generate(mem).code);
  });

  it("nested if statements needs block", function() {
    const ifStatement = t.ifStatement(
      t.stringLiteral("top cond"),
      t.whileStatement(
        t.stringLiteral("while cond"),
        t.ifStatement(
          t.stringLiteral("nested"),
          t.expressionStatement(t.numericLiteral(1)),
        ),
      ),
      t.expressionStatement(t.stringLiteral("alt")),
    );

    const ast = parse(generate(ifStatement).code);
    expect(ast.program.body[0].consequent.type).toBe("BlockStatement");
  });

  it("prints directives in block with empty body", function() {
    const blockStatement = t.blockStatement(
      [],
      [t.directive(t.directiveLiteral("use strict"))],
    );

    const output = generate(blockStatement).code;
    expect(output).toBe(`{
  "use strict";
}`);
  });

  it("flow object indentation", function() {
    const objectStatement = t.objectTypeAnnotation(
      [t.objectTypeProperty(t.identifier("bar"), t.stringTypeAnnotation())],
      null,
      null,
      null,
    );

    const output = generate(objectStatement).code;
    expect(output).toBe(`{
  bar: string
}`);
  });

  it("flow object exact", function() {
    const objectStatement = t.objectTypeAnnotation(
      [t.objectTypeProperty(t.identifier("bar"), t.stringTypeAnnotation())],
      null,
      null,
      null,
      true,
    );

    const output = generate(objectStatement).code;
    expect(output).toBe(`{|
  bar: string
|}`);
  });

  it("flow object indentation with empty leading ObjectTypeProperty", function() {
    const objectStatement = t.objectTypeAnnotation(
      [],
      [
        t.objectTypeIndexer(
          t.identifier("key"),
          t.anyTypeAnnotation(),
          t.numberTypeAnnotation(),
        ),
      ],
      null,
    );

    const output = generate(objectStatement).code;

    expect(output).toBe(`{
  [key: any]: number
}`);
  });

  describe("directives", function() {
    it("preserves escapes", function() {
      const directive = t.directive(
        t.directiveLiteral(String.raw`us\x65 strict`),
      );
      const output = generate(directive).code;

      expect(output).toBe(String.raw`"us\x65 strict";`);
    });

    it("preserves escapes in minified output", function() {
      // https://github.com/babel/babel/issues/4767

      const directive = t.directive(t.directiveLiteral(String.raw`foo\n\t\r`));
      const output = generate(directive, { minified: true }).code;

      expect(output).toBe(String.raw`"foo\n\t\r";`);
    });

    it("unescaped single quote", function() {
      const directive = t.directive(t.directiveLiteral(String.raw`'\'\"`));
      const output = generate(directive).code;

      expect(output).toBe(String.raw`"'\'\"";`);
    });

    it("unescaped double quote", function() {
      const directive = t.directive(t.directiveLiteral(String.raw`"\'\"`));
      const output = generate(directive).code;

      expect(output).toBe(String.raw`'"\'\"';`);
    });

    it("unescaped single and double quotes together throw", function() {
      const directive = t.directive(t.directiveLiteral(String.raw`'"`));

      expect(() => {
        generate(directive);
      }).toThrow();
    });
  });

  describe("typescript generate parentheses if necessary", function() {
    it("wraps around union for array", () => {
      const typeStatement = t.TSArrayType(
        t.TSUnionType([
          t.TSIntersectionType([t.TSNumberKeyword(), t.TSBooleanKeyword()]),
          t.TSNullKeyword(),
        ]),
      );
      const output = generate(typeStatement).code;
      expect(output).toBe("((number & boolean) | null)[]");
    });
    it("wraps around intersection for array", () => {
      const typeStatement = t.TSArrayType(
        t.TSIntersectionType([t.TSNumberKeyword(), t.TSBooleanKeyword()]),
      );
      const output = generate(typeStatement).code;
      expect(output).toBe("(number & boolean)[]");
    });
    it("wraps around rest", () => {
      const typeStatement = t.tsRestType(
        t.TSIntersectionType([t.TSNumberKeyword(), t.TSBooleanKeyword()]),
      );
      const output = generate(typeStatement).code;
      expect(output).toBe("...(number & boolean)");
    });
    it("wraps around optional type", () => {
      const typeStatement = t.tsOptionalType(
        t.TSIntersectionType([t.TSNumberKeyword(), t.TSBooleanKeyword()]),
      );
      const output = generate(typeStatement).code;
      expect(output).toBe("(number & boolean)?");
    });
  });
});

describe("CodeGenerator", function() {
  it("generate", function() {
    const codeGen = new CodeGenerator(t.numericLiteral(123));
    const code = codeGen.generate().code;
    expect(parse(code).program.body[0].expression.value).toBe(123);
  });
});

const suites = fixtures(`${__dirname}/fixtures`);

suites.forEach(function(testSuite) {
  describe("generation/" + testSuite.title, function() {
    testSuite.tests.forEach(function(task) {
      const testFn = task.disabled ? it.skip : it;

      testFn(
        task.title,

        function() {
          const expected = task.expect;
          const actual = task.actual;
          const actualCode = actual.code;

          if (actualCode) {
            const actualAst = parse(actualCode, {
              filename: actual.loc,
              plugins: task.options.plugins || [],
              strictMode: task.options.strictMode === false ? false : true,
              sourceType: "module",
              sourceMaps: !!task.sourceMap,
              ...task.options.parserOpts,
            });
            const options = {
              sourceFileName: path.relative(__dirname, actual.loc),
              ...task.options,
              sourceMaps: task.sourceMap ? true : task.options.sourceMaps,
            };

            function run() {
              return generate(actualAst, options, actualCode);
            }

            const throwMsg = task.options.throws;
            if (throwMsg) {
              expect(() => run()).toThrow(
                throwMsg === true ? undefined : throwMsg,
              );
            } else {
              const result = run();

              if (options.sourceMaps) {
                expect(result.map).toEqual(task.sourceMap);
              }

              if (
                !expected.code &&
                result.code &&
                fs.statSync(path.dirname(expected.loc)).isDirectory() &&
                !process.env.CI
              ) {
                console.log(`New test file created: ${expected.loc}`);
                fs.writeFileSync(expected.loc, result.code);
              } else {
                expect(result.code).toBe(expected.code);
              }
            }
          }
        },
      );
    });
  });
});