Merge pull request #12 from jsonjoy-com/copilot/fix-11

[WIP] Refactor type `random()` methods

Author: streamich

src/__tests__/fixtures.ts

@@ -0,0 +1,72 @@
+/**
+ * Fixture schemas for testing random value generation.
+ * These schemas represent different JSON Type configurations that can be used
+ * across multiple test modules.
+ */
+
+import {s} from '../schema';
+
+/**
+ * Basic primitive type schemas
+ */
+export const primitiveSchemas = {
+  string: s.String(),
+  stringWithMinMax: s.String({min: 5, max: 10}),
+  number: s.Number(),
+  numberWithFormat: s.Number({format: 'u32'}),
+  numberWithRange: s.Number({gte: 0, lte: 100}),
+  boolean: s.Boolean(),
+  const: s.Const('fixed-value' as const),
+  any: s.Any(),
+} as const;
+
+/**
+ * Complex composite type schemas
+ */
+export const compositeSchemas = {
+  simpleArray: s.Array(s.String()),
+  arrayWithBounds: s.Array(s.Number(), {min: 2, max: 5}),
+  simpleObject: s.Object([s.prop('id', s.String()), s.prop('name', s.String()), s.prop('active', s.Boolean())]),
+  objectWithOptionalFields: s.Object([
+    s.prop('id', s.String()),
+    s.propOpt('name', s.String()),
+    s.propOpt('count', s.Number()),
+  ]),
+  nestedObject: s.Object([
+    s.prop(
+      'user',
+      s.Object([
+        s.prop('id', s.Number()),
+        s.prop('profile', s.Object([s.prop('name', s.String()), s.prop('email', s.String())])),
+      ]),
+    ),
+    s.prop('tags', s.Array(s.String())),
+  ]),
+  tuple: s.Tuple(s.String(), s.Number(), s.Boolean()),
+  map: s.Map(s.String()),
+  mapWithComplexValue: s.Map(s.Object([s.prop('value', s.Number()), s.prop('label', s.String())])),
+  union: s.Or(s.String(), s.Number(), s.Boolean()),
+  complexUnion: s.Or(
+    s.String(),
+    s.Object([s.prop('type', s.Const('object' as const)), s.prop('data', s.Any())]),
+    s.Array(s.Number()),
+  ),
+  binary: s.bin,
+} as const;
+
+/**
+ * All fixture schemas combined for comprehensive testing
+ */
+export const allSchemas = {
+  ...primitiveSchemas,
+  ...compositeSchemas,
+} as const;
+
+/**
+ * Schema categories for organized testing
+ */
+export const schemaCategories = {
+  primitives: primitiveSchemas,
+  composites: compositeSchemas,
+  all: allSchemas,
+} as const;

src/random/__tests__/random.spec.ts

@@ -0,0 +1,285 @@
+/**
+ * Unit tests for the src/random/ module.
+ * Tests that generated random values conform to their JSON Type schemas.
+ */
+
+import {t} from '../../type';
+import {allSchemas, schemaCategories} from '../../__tests__/fixtures';
+import * as gen from '../generators';
+import {random} from '../generator';
+
+describe('random generators', () => {
+  describe('individual generator functions', () => {
+    describe('primitives', () => {
+      test('str generates valid strings', () => {
+        const type = t.String();
+        for (let i = 0; i < 10; i++) {
+          const value = gen.str(type);
+          expect(typeof value).toBe('string');
+          type.validate(value);
+        }
+      });
+
+      test('str respects min/max constraints', () => {
+        const type = t.String({min: 5, max: 10});
+        for (let i = 0; i < 10; i++) {
+          const value = gen.str(type);
+          expect(typeof value).toBe('string');
+          expect(value.length).toBeGreaterThanOrEqual(5);
+          expect(value.length).toBeLessThanOrEqual(10);
+          type.validate(value);
+        }
+      });
+
+      test('num generates valid numbers', () => {
+        const type = t.Number();
+        for (let i = 0; i < 10; i++) {
+          const value = gen.num(type);
+          expect(typeof value).toBe('number');
+          type.validate(value);
+        }
+      });
+
+      test('num respects format constraints', () => {
+        const type = t.Number({format: 'u32'});
+        for (let i = 0; i < 10; i++) {
+          const value = gen.num(type);
+          expect(typeof value).toBe('number');
+          expect(Number.isInteger(value)).toBe(true);
+          expect(value).toBeGreaterThanOrEqual(0);
+          expect(value).toBeLessThanOrEqual(0xffffffff);
+          type.validate(value);
+        }
+      });
+
+      test('bool generates valid booleans', () => {
+        const type = t.Boolean();
+        for (let i = 0; i < 10; i++) {
+          const value = gen.bool(type);
+          expect(typeof value).toBe('boolean');
+          type.validate(value);
+        }
+      });
+
+      test('const_ generates exact values', () => {
+        const type = t.Const('fixed-value' as const);
+        for (let i = 0; i < 10; i++) {
+          const value = gen.const_(type);
+          expect(value).toBe('fixed-value');
+          type.validate(value);
+        }
+      });
+
+      test('any generates valid JSON values', () => {
+        const type = t.Any();
+        for (let i = 0; i < 10; i++) {
+          const value = gen.any(type);
+          expect(value).toBeDefined();
+          type.validate(value);
+        }
+      });
+
+      test('bin generates Uint8Array', () => {
+        const type = t.bin;
+        for (let i = 0; i < 10; i++) {
+          const value = gen.bin(type);
+          expect(value).toBeInstanceOf(Uint8Array);
+          type.validate(value);
+        }
+      });
+    });
+
+    describe('composites', () => {
+      test('arr generates valid arrays', () => {
+        const type = t.Array(t.String());
+        for (let i = 0; i < 10; i++) {
+          const value = gen.arr(type);
+          expect(Array.isArray(value)).toBe(true);
+          type.validate(value);
+        }
+      });
+
+      test('arr respects min/max constraints', () => {
+        const type = t.Array(t.String(), {min: 2, max: 5});
+        for (let i = 0; i < 10; i++) {
+          const value = gen.arr(type);
+          expect(Array.isArray(value)).toBe(true);
+          expect(value.length).toBeGreaterThanOrEqual(2);
+          expect(value.length).toBeLessThanOrEqual(5);
+          type.validate(value);
+        }
+      });
+
+      test('obj generates valid objects', () => {
+        const type = t.Object(t.prop('id', t.String()), t.prop('count', t.Number()));
+        for (let i = 0; i < 10; i++) {
+          const value = gen.obj(type);
+          expect(typeof value).toBe('object');
+          expect(value).not.toBeNull();
+          expect(value).not.toBeInstanceOf(Array);
+          expect(value).toHaveProperty('id');
+          expect(value).toHaveProperty('count');
+          type.validate(value);
+        }
+      });
+
+      test('tup generates valid tuples', () => {
+        const type = t.Tuple(t.String(), t.Number(), t.Boolean());
+        for (let i = 0; i < 10; i++) {
+          const value = gen.tup(type);
+          expect(Array.isArray(value)).toBe(true);
+          expect(value).toHaveLength(3);
+          expect(typeof value[0]).toBe('string');
+          expect(typeof value[1]).toBe('number');
+          expect(typeof value[2]).toBe('boolean');
+          type.validate(value);
+        }
+      });
+
+      test('map generates valid maps', () => {
+        const type = t.Map(t.String());
+        for (let i = 0; i < 10; i++) {
+          const value = gen.map(type);
+          expect(typeof value).toBe('object');
+          expect(value).not.toBeNull();
+          expect(value).not.toBeInstanceOf(Array);
+          type.validate(value);
+        }
+      });
+
+      test('or generates values from union types', () => {
+        const type = t.Or(t.String(), t.Number());
+        const generatedTypes = new Set<string>();
+
+        for (let i = 0; i < 20; i++) {
+          const value = gen.or(type);
+          generatedTypes.add(typeof value);
+          type.validate(value);
+        }
+
+        // Should generate at least one of each type over multiple iterations
+        expect(generatedTypes.size).toBeGreaterThan(0);
+      });
+
+      test('fn generates async functions', async () => {
+        const type = t.Function(t.num, t.String());
+        const value = gen.fn(type);
+        expect(typeof value).toBe('function');
+
+        // Test that the function is async and returns the expected type
+        const result = await (value as () => Promise<unknown>)();
+        expect(typeof result).toBe('string');
+      });
+    });
+  });
+
+  describe('main router function', () => {
+    test('dispatches to correct generators for all types', () => {
+      for (const [name, schema] of Object.entries(schemaCategories.primitives)) {
+        const type = t.from(schema);
+        for (let i = 0; i < 5; i++) {
+          const value = random(type);
+          expect(() => type.validate(value)).not.toThrow();
+        }
+      }
+
+      for (const [name, schema] of Object.entries(schemaCategories.composites)) {
+        const type = t.from(schema);
+        for (let i = 0; i < 5; i++) {
+          const value = random(type);
+          expect(() => type.validate(value)).not.toThrow();
+        }
+      }
+    });
+  });
+
+  describe('comprehensive schema validation', () => {
+    test('generated values pass validation for all fixture schemas', () => {
+      for (const [name, schema] of Object.entries(allSchemas)) {
+        const type = t.from(schema);
+
+        // Test multiple random generations for each schema
+        for (let i = 0; i < 10; i++) {
+          const randomValue = type.random();
+
+          // Test using both validate methods
+          expect(() => type.validate(randomValue)).not.toThrow();
+
+          // Test using compiled validator
+          const validator = type.compileValidator({errors: 'object'});
+          const error = validator(randomValue);
+          expect(error).toBe(null);
+        }
+      }
+    });
+
+    test('handles nested complex structures', () => {
+      const complexType = t.Object(
+        t.prop(
+          'users',
+          t.Array(
+            t.Object(
+              t.prop('id', t.Number()),
+              t.prop(
+                'profile',
+                t.Object(t.prop('name', t.String()), t.prop('preferences', t.Map(t.Or(t.String(), t.Boolean())))),
+              ),
+              t.propOpt('tags', t.Array(t.String())),
+            ),
+          ),
+        ),
+        t.prop('metadata', t.Map(t.Any())),
+        t.prop('config', t.Tuple(t.String(), t.Number(), t.Object(t.prop('enabled', t.Boolean())))),
+      );
+
+      for (let i = 0; i < 5; i++) {
+        const value = complexType.random();
+        expect(() => complexType.validate(value)).not.toThrow();
+      }
+    });
+
+    test('handles edge cases and constraints', () => {
+      // Empty array constraint
+      const emptyArrayType = t.Array(t.String(), {max: 0});
+      const emptyArray = emptyArrayType.random();
+      expect(emptyArray).toEqual([]);
+      emptyArrayType.validate(emptyArray);
+
+      // Single item array constraint
+      const singleItemType = t.Array(t.Number(), {min: 1, max: 1});
+      const singleItem = singleItemType.random();
+      expect(singleItem).toHaveLength(1);
+      singleItemType.validate(singleItem);
+
+      // Number with tight range
+      const tightRangeType = t.Number({gte: 5, lte: 5});
+      const tightRangeValue = tightRangeType.random();
+      expect(tightRangeValue).toBe(5);
+      tightRangeType.validate(tightRangeValue);
+    });
+  });
+
+  describe('deterministic behavior with controlled randomness', () => {
+    test('generates consistent values with mocked Math.random', () => {
+      const originalRandom = Math.random;
+      let callCount = 0;
+      Math.random = () => {
+        callCount++;
+        return 0.5; // Always return 0.5 for predictable results
+      };
+
+      try {
+        const type = t.String({min: 5, max: 5});
+        const value1 = type.random();
+        const value2 = type.random();
+
+        // With fixed random, string generation should be consistent
+        expect(value1).toBe(value2);
+        expect(value1).toHaveLength(5);
+        type.validate(value1);
+      } finally {
+        Math.random = originalRandom;
+      }
+    });
+  });
+});