File size: 14,547 Bytes
fd8cdf5
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
import { describe, it, expect } from 'vitest';
import { buildTour, findEntryPoint } from './tour-builder';
function makeFileNode(id, name, summary, tags) {
    return {
        id,
        type: 'file',
        name: name ?? id.split('/').pop(),
        summary: summary ?? `Source file: ${id}`,
        tags: tags ?? ['typescript'],
    };
}
function makeFunctionNode(fileId, funcName) {
    return {
        id: `${fileId}::${funcName}`,
        type: 'function',
        name: funcName,
        summary: `() → 15 lines`,
        tags: ['typescript', 'exported'],
    };
}
function makeImportEdge(source, target) {
    return { source, target, type: 'imports' };
}
function makeContainsEdge(source, target) {
    return { source, target, type: 'contains' };
}
function makeLayer(id, name, nodeIds) {
    return { id, name, description: `${name} layer`, nodeIds };
}
describe('findEntryPoint', () => {
    it('finds index.ts at root level', () => {
        const nodes = [
            makeFileNode('index.ts'),
            makeFileNode('src/utils.ts'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('index.ts');
    });
    it('finds index.ts in src/ directory', () => {
        const nodes = [
            makeFileNode('src/index.ts', 'index.ts'),
            makeFileNode('src/utils.ts'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('src/index.ts');
    });
    it('finds main.ts when no index.ts exists', () => {
        const nodes = [
            makeFileNode('src/main.ts', 'main.ts'),
            makeFileNode('src/utils.ts'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('src/main.ts');
    });
    it('finds App.tsx when no index or main exists', () => {
        const nodes = [
            makeFileNode('src/App.tsx', 'App.tsx'),
            makeFileNode('src/utils.ts'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('src/App.tsx');
    });
    it('finds main.py for Python projects', () => {
        const nodes = [
            makeFileNode('main.py', 'main.py'),
            makeFileNode('utils.py'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('main.py');
    });
    it('finds main.go for Go projects', () => {
        const nodes = [
            makeFileNode('main.go', 'main.go'),
            makeFileNode('handler.go'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('main.go');
    });
    it('prioritizes index.ts over main.ts', () => {
        const nodes = [
            makeFileNode('src/main.ts', 'main.ts'),
            makeFileNode('src/index.ts', 'index.ts'),
        ];
        const result = findEntryPoint(nodes, []);
        expect(result?.id).toBe('src/index.ts');
    });
    it('falls back to file with most outgoing import edges', () => {
        const nodes = [
            makeFileNode('src/app.module.ts'),
            makeFileNode('src/service.ts'),
            makeFileNode('src/helper.ts'),
        ];
        const edges = [
            makeImportEdge('src/app.module.ts', 'src/service.ts'),
            makeImportEdge('src/app.module.ts', 'src/helper.ts'),
            makeImportEdge('src/service.ts', 'src/helper.ts'),
        ];
        const result = findEntryPoint(nodes, edges);
        expect(result?.id).toBe('src/app.module.ts');
    });
    it('returns undefined for empty nodes', () => {
        const result = findEntryPoint([], []);
        expect(result).toBeUndefined();
    });
});
describe('buildTour', () => {
    describe('BFS traversal', () => {
        it('builds tour following import edges from entry point', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFileNode('src/app.ts', 'app.ts'),
                makeFileNode('src/utils.ts', 'utils.ts'),
            ];
            const edges = [
                makeImportEdge('src/index.ts', 'src/app.ts'),
                makeImportEdge('src/app.ts', 'src/utils.ts'),
            ];
            const layers = [];
            const tour = buildTour(nodes, edges, layers);
            expect(tour).toHaveLength(3);
            expect(tour[0].order).toBe(1);
            expect(tour[0].title).toBe('index.ts');
            expect(tour[0].nodeIds).toContain('src/index.ts');
            expect(tour[1].order).toBe(2);
            expect(tour[1].title).toBe('app.ts');
            expect(tour[2].order).toBe(3);
            expect(tour[2].title).toBe('utils.ts');
        });
        it('does not revisit files (no duplicates)', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFileNode('src/a.ts', 'a.ts'),
                makeFileNode('src/b.ts', 'b.ts'),
            ];
            const edges = [
                makeImportEdge('src/index.ts', 'src/a.ts'),
                makeImportEdge('src/index.ts', 'src/b.ts'),
                makeImportEdge('src/a.ts', 'src/b.ts'), // b already visited via index
            ];
            const layers = [];
            const tour = buildTour(nodes, edges, layers);
            const fileIds = tour.map(s => s.nodeIds[0]);
            const uniqueIds = new Set(fileIds);
            expect(fileIds.length).toBe(uniqueIds.size);
        });
        it('limits tour to 10 steps maximum', () => {
            const nodes = [];
            const edges = [];
            // Create a chain of 15 files
            for (let i = 0; i < 15; i++) {
                const id = i === 0 ? 'src/index.ts' : `src/file${i}.ts`;
                nodes.push(makeFileNode(id, id.split('/').pop()));
                if (i > 0) {
                    const prevId = i === 1 ? 'src/index.ts' : `src/file${i - 1}.ts`;
                    edges.push(makeImportEdge(prevId, id));
                }
            }
            const tour = buildTour(nodes, edges, []);
            expect(tour.length).toBeLessThanOrEqual(10);
        });
    });
    describe('step generation', () => {
        it('generates correct order, title, description, and nodeIds', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts', 'Exports: main, init'),
                makeFunctionNode('src/index.ts', 'main'),
            ];
            const edges = [
                makeContainsEdge('src/index.ts', 'src/index.ts::main'),
            ];
            const layers = [makeLayer('root', 'Root', ['src/index.ts'])];
            const tour = buildTour(nodes, edges, layers);
            expect(tour).toHaveLength(1);
            expect(tour[0].order).toBe(1);
            expect(tour[0].title).toBe('index.ts');
            expect(tour[0].description).toContain('Exports: main, init');
            expect(tour[0].description).toContain('Root');
            expect(tour[0].nodeIds).toContain('src/index.ts');
            expect(tour[0].nodeIds).toContain('src/index.ts::main');
        });
        it('includes child function/class nodes in nodeIds', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFunctionNode('src/index.ts', 'setup'),
                makeFunctionNode('src/index.ts', 'teardown'),
            ];
            const edges = [];
            const layers = [];
            const tour = buildTour(nodes, edges, layers);
            expect(tour[0].nodeIds).toContain('src/index.ts');
            expect(tour[0].nodeIds).toContain('src/index.ts::setup');
            expect(tour[0].nodeIds).toContain('src/index.ts::teardown');
        });
        it('generates description with layer info when available', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts', 'Entry point'),
            ];
            const edges = [];
            const layers = [makeLayer('presentation', 'Presentation', ['src/index.ts'])];
            const tour = buildTour(nodes, edges, layers);
            expect(tour[0].description).toContain('Presentation');
        });
    });
    describe('layer-based supplementation', () => {
        it('supplements with layer representatives when BFS produces fewer than 5 steps', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFileNode('src/components/Button.tsx', 'Button.tsx'),
                makeFileNode('src/models/User.ts', 'User.ts'),
                makeFileNode('src/utils/format.ts', 'format.ts'),
                makeFileNode('src/api/routes.ts', 'routes.ts'),
            ];
            // Only one import edge from entry point (BFS gives 2 steps)
            const edges = [
                makeImportEdge('src/index.ts', 'src/components/Button.tsx'),
                // Give other files some edges so they get picked
                makeImportEdge('src/models/User.ts', 'src/utils/format.ts'),
                makeImportEdge('src/api/routes.ts', 'src/models/User.ts'),
            ];
            const layers = [
                makeLayer('root', 'Root', ['src/index.ts']),
                makeLayer('presentation', 'Presentation', ['src/components/Button.tsx']),
                makeLayer('data', 'Data', ['src/models/User.ts']),
                makeLayer('utilities', 'Utilities', ['src/utils/format.ts']),
                makeLayer('api', 'API', ['src/api/routes.ts']),
            ];
            const tour = buildTour(nodes, edges, layers);
            // BFS gives index.ts + Button.tsx = 2 steps
            // Supplementation should add from uncovered layers (data, utilities, api)
            expect(tour.length).toBeGreaterThanOrEqual(4);
            const tourFileIds = tour.map(s => s.nodeIds[0]);
            expect(tourFileIds).toContain('src/index.ts');
            expect(tourFileIds).toContain('src/components/Button.tsx');
        });
        it('picks most connected file from each uncovered layer', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFileNode('src/utils/a.ts', 'a.ts'),
                makeFileNode('src/utils/b.ts', 'b.ts'),
            ];
            const edges = [
                // b.ts has more edges than a.ts
                makeImportEdge('src/utils/b.ts', 'src/utils/a.ts'),
                makeImportEdge('src/index.ts', 'src/utils/b.ts'),
            ];
            const layers = [
                makeLayer('root', 'Root', ['src/index.ts']),
                makeLayer('utilities', 'Utilities', ['src/utils/a.ts', 'src/utils/b.ts']),
            ];
            const tour = buildTour(nodes, edges, layers);
            // BFS from index.ts → b.ts → a.ts (3 steps, all covered)
            // Since BFS < 5, supplementation runs but utilities layer is already covered
            const tourFileIds = tour.map(s => s.nodeIds[0]);
            expect(tourFileIds).toContain('src/index.ts');
            expect(tourFileIds).toContain('src/utils/b.ts');
        });
        it('does not supplement when BFS produces 5 or more steps', () => {
            const nodes = [];
            const edges = [];
            // Create a chain of 6 files from entry point
            for (let i = 0; i < 6; i++) {
                const id = i === 0 ? 'src/index.ts' : `src/file${i}.ts`;
                nodes.push(makeFileNode(id, id.split('/').pop()));
                if (i > 0) {
                    const prevId = i === 1 ? 'src/index.ts' : `src/file${i - 1}.ts`;
                    edges.push(makeImportEdge(prevId, id));
                }
            }
            // Add an extra file in a different layer that's NOT reachable via BFS
            nodes.push(makeFileNode('src/extra/orphan.ts', 'orphan.ts'));
            const layers = [
                makeLayer('main', 'Main', nodes.slice(0, 6).map(n => n.id)),
                makeLayer('extra', 'Extra', ['src/extra/orphan.ts']),
            ];
            const tour = buildTour(nodes, edges, layers);
            // BFS gives 6 steps (>= 5), so no supplementation
            const tourFileIds = tour.map(s => s.nodeIds[0]);
            expect(tourFileIds).not.toContain('src/extra/orphan.ts');
            expect(tour).toHaveLength(6);
        });
    });
    describe('edge cases', () => {
        it('returns empty array for empty nodes', () => {
            const tour = buildTour([], [], []);
            expect(tour).toEqual([]);
        });
        it('returns empty array when no file nodes exist', () => {
            const nodes = [
                makeFunctionNode('src/index.ts', 'main'),
            ];
            const tour = buildTour(nodes, [], []);
            expect(tour).toEqual([]);
        });
        it('returns one step for a single file', () => {
            const nodes = [makeFileNode('src/index.ts', 'index.ts')];
            const tour = buildTour(nodes, [], []);
            expect(tour).toHaveLength(1);
            expect(tour[0].order).toBe(1);
            expect(tour[0].title).toBe('index.ts');
            expect(tour[0].nodeIds).toContain('src/index.ts');
        });
        it('handles files with no import edges (isolated nodes)', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFileNode('src/isolated.ts', 'isolated.ts'),
            ];
            const edges = [];
            const layers = [];
            const tour = buildTour(nodes, edges, layers);
            // BFS from index.ts finds only index.ts (no edges)
            // With no layers, supplementation doesn't add anything
            expect(tour).toHaveLength(1);
            expect(tour[0].nodeIds[0]).toBe('src/index.ts');
        });
        it('handles circular import references gracefully', () => {
            const nodes = [
                makeFileNode('src/index.ts', 'index.ts'),
                makeFileNode('src/a.ts', 'a.ts'),
                makeFileNode('src/b.ts', 'b.ts'),
            ];
            const edges = [
                makeImportEdge('src/index.ts', 'src/a.ts'),
                makeImportEdge('src/a.ts', 'src/b.ts'),
                makeImportEdge('src/b.ts', 'src/a.ts'), // circular
            ];
            const tour = buildTour(nodes, edges, []);
            // Should not loop infinitely, each file appears once
            expect(tour).toHaveLength(3);
            const fileIds = tour.map(s => s.nodeIds[0]);
            expect(new Set(fileIds).size).toBe(3);
        });
    });
});