1 | // Copyright 2018 The Go Authors. All rights reserved. |
---|---|
2 | // Use of this source code is governed by a BSD-style |
3 | // license that can be found in the LICENSE file. |
4 | |
5 | package packagestest |
6 | |
7 | import ( |
8 | "fmt" |
9 | "go/token" |
10 | "io/ioutil" |
11 | "os" |
12 | "path/filepath" |
13 | "reflect" |
14 | "regexp" |
15 | "strings" |
16 | |
17 | "golang.org/x/tools/go/expect" |
18 | "golang.org/x/tools/go/packages" |
19 | ) |
20 | |
21 | const ( |
22 | markMethod = "mark" |
23 | eofIdentifier = "EOF" |
24 | ) |
25 | |
26 | // Expect invokes the supplied methods for all expectation notes found in |
27 | // the exported source files. |
28 | // |
29 | // All exported go source files are parsed to collect the expectation |
30 | // notes. |
31 | // See the documentation for expect.Parse for how the notes are collected |
32 | // and parsed. |
33 | // |
34 | // The methods are supplied as a map of name to function, and those functions |
35 | // will be matched against the expectations by name. |
36 | // Notes with no matching function will be skipped, and functions with no |
37 | // matching notes will not be invoked. |
38 | // If there are no registered markers yet, a special pass will be run first |
39 | // which adds any markers declared with @mark(Name, pattern) or @name. These |
40 | // call the Mark method to add the marker to the global set. |
41 | // You can register the "mark" method to override these in your own call to |
42 | // Expect. The bound Mark function is usable directly in your method map, so |
43 | // |
44 | // exported.Expect(map[string]interface{}{"mark": exported.Mark}) |
45 | // |
46 | // replicates the built in behavior. |
47 | // |
48 | // # Method invocation |
49 | // |
50 | // When invoking a method the expressions in the parameter list need to be |
51 | // converted to values to be passed to the method. |
52 | // There are a very limited set of types the arguments are allowed to be. |
53 | // |
54 | // expect.Note : passed the Note instance being evaluated. |
55 | // string : can be supplied either a string literal or an identifier. |
56 | // int : can only be supplied an integer literal. |
57 | // *regexp.Regexp : can only be supplied a regular expression literal |
58 | // token.Pos : has a file position calculated as described below. |
59 | // token.Position : has a file position calculated as described below. |
60 | // expect.Range: has a start and end position as described below. |
61 | // interface{} : will be passed any value |
62 | // |
63 | // # Position calculation |
64 | // |
65 | // There is some extra handling when a parameter is being coerced into a |
66 | // token.Pos, token.Position or Range type argument. |
67 | // |
68 | // If the parameter is an identifier, it will be treated as the name of an |
69 | // marker to look up (as if markers were global variables). |
70 | // |
71 | // If it is a string or regular expression, then it will be passed to |
72 | // expect.MatchBefore to look up a match in the line at which it was declared. |
73 | // |
74 | // It is safe to call this repeatedly with different method sets, but it is |
75 | // not safe to call it concurrently. |
76 | func (e *Exported) Expect(methods map[string]interface{}) error { |
77 | if err := e.getNotes(); err != nil { |
78 | return err |
79 | } |
80 | if err := e.getMarkers(); err != nil { |
81 | return err |
82 | } |
83 | var err error |
84 | ms := make(map[string]method, len(methods)) |
85 | for name, f := range methods { |
86 | mi := method{f: reflect.ValueOf(f)} |
87 | mi.converters = make([]converter, mi.f.Type().NumIn()) |
88 | for i := 0; i < len(mi.converters); i++ { |
89 | mi.converters[i], err = e.buildConverter(mi.f.Type().In(i)) |
90 | if err != nil { |
91 | return fmt.Errorf("invalid method %v: %v", name, err) |
92 | } |
93 | } |
94 | ms[name] = mi |
95 | } |
96 | for _, n := range e.notes { |
97 | if n.Args == nil { |
98 | // simple identifier form, convert to a call to mark |
99 | n = &expect.Note{ |
100 | Pos: n.Pos, |
101 | Name: markMethod, |
102 | Args: []interface{}{n.Name, n.Name}, |
103 | } |
104 | } |
105 | mi, ok := ms[n.Name] |
106 | if !ok { |
107 | continue |
108 | } |
109 | params := make([]reflect.Value, len(mi.converters)) |
110 | args := n.Args |
111 | for i, convert := range mi.converters { |
112 | params[i], args, err = convert(n, args) |
113 | if err != nil { |
114 | return fmt.Errorf("%v: %v", e.ExpectFileSet.Position(n.Pos), err) |
115 | } |
116 | } |
117 | if len(args) > 0 { |
118 | return fmt.Errorf("%v: unwanted args got %+v extra", e.ExpectFileSet.Position(n.Pos), args) |
119 | } |
120 | //TODO: catch the error returned from the method |
121 | mi.f.Call(params) |
122 | } |
123 | return nil |
124 | } |
125 | |
126 | // A Range represents an interval within a source file in go/token notation. |
127 | type Range struct { |
128 | TokFile *token.File // non-nil |
129 | Start, End token.Pos // both valid and within range of TokFile |
130 | } |
131 | |
132 | // A rangeSetter abstracts a variable that can be set from a Range value. |
133 | // |
134 | // The parameter conversion machinery will automatically construct a |
135 | // variable of type T and call the SetRange method on its address if |
136 | // *T implements rangeSetter. This allows alternative notations of |
137 | // source ranges to interoperate transparently with this package. |
138 | // |
139 | // This type intentionally does not mention Range itself, to avoid a |
140 | // dependency from the application's range type upon this package. |
141 | // |
142 | // Currently this is a secret back door for use only by gopls. |
143 | type rangeSetter interface { |
144 | SetRange(file *token.File, start, end token.Pos) |
145 | } |
146 | |
147 | // Mark adds a new marker to the known set. |
148 | func (e *Exported) Mark(name string, r Range) { |
149 | if e.markers == nil { |
150 | e.markers = make(map[string]Range) |
151 | } |
152 | e.markers[name] = r |
153 | } |
154 | |
155 | func (e *Exported) getNotes() error { |
156 | if e.notes != nil { |
157 | return nil |
158 | } |
159 | notes := []*expect.Note{} |
160 | var dirs []string |
161 | for _, module := range e.written { |
162 | for _, filename := range module { |
163 | dirs = append(dirs, filepath.Dir(filename)) |
164 | } |
165 | } |
166 | for filename := range e.Config.Overlay { |
167 | dirs = append(dirs, filepath.Dir(filename)) |
168 | } |
169 | pkgs, err := packages.Load(e.Config, dirs...) |
170 | if err != nil { |
171 | return fmt.Errorf("unable to load packages for directories %s: %v", dirs, err) |
172 | } |
173 | seen := make(map[token.Position]struct{}) |
174 | for _, pkg := range pkgs { |
175 | for _, filename := range pkg.GoFiles { |
176 | content, err := e.FileContents(filename) |
177 | if err != nil { |
178 | return err |
179 | } |
180 | l, err := expect.Parse(e.ExpectFileSet, filename, content) |
181 | if err != nil { |
182 | return fmt.Errorf("failed to extract expectations: %v", err) |
183 | } |
184 | for _, note := range l { |
185 | pos := e.ExpectFileSet.Position(note.Pos) |
186 | if _, ok := seen[pos]; ok { |
187 | continue |
188 | } |
189 | notes = append(notes, note) |
190 | seen[pos] = struct{}{} |
191 | } |
192 | } |
193 | } |
194 | if _, ok := e.written[e.primary]; !ok { |
195 | e.notes = notes |
196 | return nil |
197 | } |
198 | // Check go.mod markers regardless of mode, we need to do this so that our marker count |
199 | // matches the counts in the summary.txt.golden file for the test directory. |
200 | if gomod, found := e.written[e.primary]["go.mod"]; found { |
201 | // If we are in Modules mode, then we need to check the contents of the go.mod.temp. |
202 | if e.Exporter == Modules { |
203 | gomod += ".temp" |
204 | } |
205 | l, err := goModMarkers(e, gomod) |
206 | if err != nil { |
207 | return fmt.Errorf("failed to extract expectations for go.mod: %v", err) |
208 | } |
209 | notes = append(notes, l...) |
210 | } |
211 | e.notes = notes |
212 | return nil |
213 | } |
214 | |
215 | func goModMarkers(e *Exported, gomod string) ([]*expect.Note, error) { |
216 | if _, err := os.Stat(gomod); os.IsNotExist(err) { |
217 | // If there is no go.mod file, we want to be able to continue. |
218 | return nil, nil |
219 | } |
220 | content, err := e.FileContents(gomod) |
221 | if err != nil { |
222 | return nil, err |
223 | } |
224 | if e.Exporter == GOPATH { |
225 | return expect.Parse(e.ExpectFileSet, gomod, content) |
226 | } |
227 | gomod = strings.TrimSuffix(gomod, ".temp") |
228 | // If we are in Modules mode, copy the original contents file back into go.mod |
229 | if err := ioutil.WriteFile(gomod, content, 0644); err != nil { |
230 | return nil, nil |
231 | } |
232 | return expect.Parse(e.ExpectFileSet, gomod, content) |
233 | } |
234 | |
235 | func (e *Exported) getMarkers() error { |
236 | if e.markers != nil { |
237 | return nil |
238 | } |
239 | // set markers early so that we don't call getMarkers again from Expect |
240 | e.markers = make(map[string]Range) |
241 | return e.Expect(map[string]interface{}{ |
242 | markMethod: e.Mark, |
243 | }) |
244 | } |
245 | |
246 | var ( |
247 | noteType = reflect.TypeOf((*expect.Note)(nil)) |
248 | identifierType = reflect.TypeOf(expect.Identifier("")) |
249 | posType = reflect.TypeOf(token.Pos(0)) |
250 | positionType = reflect.TypeOf(token.Position{}) |
251 | rangeType = reflect.TypeOf(Range{}) |
252 | rangeSetterType = reflect.TypeOf((*rangeSetter)(nil)).Elem() |
253 | fsetType = reflect.TypeOf((*token.FileSet)(nil)) |
254 | regexType = reflect.TypeOf((*regexp.Regexp)(nil)) |
255 | exportedType = reflect.TypeOf((*Exported)(nil)) |
256 | ) |
257 | |
258 | // converter converts from a marker's argument parsed from the comment to |
259 | // reflect values passed to the method during Invoke. |
260 | // It takes the args remaining, and returns the args it did not consume. |
261 | // This allows a converter to consume 0 args for well known types, or multiple |
262 | // args for compound types. |
263 | type converter func(*expect.Note, []interface{}) (reflect.Value, []interface{}, error) |
264 | |
265 | // method is used to track information about Invoke methods that is expensive to |
266 | // calculate so that we can work it out once rather than per marker. |
267 | type method struct { |
268 | f reflect.Value // the reflect value of the passed in method |
269 | converters []converter // the parameter converters for the method |
270 | } |
271 | |
272 | // buildConverter works out what function should be used to go from an ast expressions to a reflect |
273 | // value of the type expected by a method. |
274 | // It is called when only the target type is know, it returns converters that are flexible across |
275 | // all supported expression types for that target type. |
276 | func (e *Exported) buildConverter(pt reflect.Type) (converter, error) { |
277 | switch { |
278 | case pt == noteType: |
279 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
280 | return reflect.ValueOf(n), args, nil |
281 | }, nil |
282 | case pt == fsetType: |
283 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
284 | return reflect.ValueOf(e.ExpectFileSet), args, nil |
285 | }, nil |
286 | case pt == exportedType: |
287 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
288 | return reflect.ValueOf(e), args, nil |
289 | }, nil |
290 | case pt == posType: |
291 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
292 | r, remains, err := e.rangeConverter(n, args) |
293 | if err != nil { |
294 | return reflect.Value{}, nil, err |
295 | } |
296 | return reflect.ValueOf(r.Start), remains, nil |
297 | }, nil |
298 | case pt == positionType: |
299 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
300 | r, remains, err := e.rangeConverter(n, args) |
301 | if err != nil { |
302 | return reflect.Value{}, nil, err |
303 | } |
304 | return reflect.ValueOf(e.ExpectFileSet.Position(r.Start)), remains, nil |
305 | }, nil |
306 | case pt == rangeType: |
307 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
308 | r, remains, err := e.rangeConverter(n, args) |
309 | if err != nil { |
310 | return reflect.Value{}, nil, err |
311 | } |
312 | return reflect.ValueOf(r), remains, nil |
313 | }, nil |
314 | case reflect.PtrTo(pt).AssignableTo(rangeSetterType): |
315 | // (*pt).SetRange method exists: call it. |
316 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
317 | r, remains, err := e.rangeConverter(n, args) |
318 | if err != nil { |
319 | return reflect.Value{}, nil, err |
320 | } |
321 | v := reflect.New(pt) |
322 | v.Interface().(rangeSetter).SetRange(r.TokFile, r.Start, r.End) |
323 | return v.Elem(), remains, nil |
324 | }, nil |
325 | case pt == identifierType: |
326 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
327 | if len(args) < 1 { |
328 | return reflect.Value{}, nil, fmt.Errorf("missing argument") |
329 | } |
330 | arg := args[0] |
331 | args = args[1:] |
332 | switch arg := arg.(type) { |
333 | case expect.Identifier: |
334 | return reflect.ValueOf(arg), args, nil |
335 | default: |
336 | return reflect.Value{}, nil, fmt.Errorf("cannot convert %v to string", arg) |
337 | } |
338 | }, nil |
339 | |
340 | case pt == regexType: |
341 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
342 | if len(args) < 1 { |
343 | return reflect.Value{}, nil, fmt.Errorf("missing argument") |
344 | } |
345 | arg := args[0] |
346 | args = args[1:] |
347 | if _, ok := arg.(*regexp.Regexp); !ok { |
348 | return reflect.Value{}, nil, fmt.Errorf("cannot convert %v to *regexp.Regexp", arg) |
349 | } |
350 | return reflect.ValueOf(arg), args, nil |
351 | }, nil |
352 | |
353 | case pt.Kind() == reflect.String: |
354 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
355 | if len(args) < 1 { |
356 | return reflect.Value{}, nil, fmt.Errorf("missing argument") |
357 | } |
358 | arg := args[0] |
359 | args = args[1:] |
360 | switch arg := arg.(type) { |
361 | case expect.Identifier: |
362 | return reflect.ValueOf(string(arg)), args, nil |
363 | case string: |
364 | return reflect.ValueOf(arg), args, nil |
365 | default: |
366 | return reflect.Value{}, nil, fmt.Errorf("cannot convert %v to string", arg) |
367 | } |
368 | }, nil |
369 | case pt.Kind() == reflect.Int64: |
370 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
371 | if len(args) < 1 { |
372 | return reflect.Value{}, nil, fmt.Errorf("missing argument") |
373 | } |
374 | arg := args[0] |
375 | args = args[1:] |
376 | switch arg := arg.(type) { |
377 | case int64: |
378 | return reflect.ValueOf(arg), args, nil |
379 | default: |
380 | return reflect.Value{}, nil, fmt.Errorf("cannot convert %v to int", arg) |
381 | } |
382 | }, nil |
383 | case pt.Kind() == reflect.Bool: |
384 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
385 | if len(args) < 1 { |
386 | return reflect.Value{}, nil, fmt.Errorf("missing argument") |
387 | } |
388 | arg := args[0] |
389 | args = args[1:] |
390 | b, ok := arg.(bool) |
391 | if !ok { |
392 | return reflect.Value{}, nil, fmt.Errorf("cannot convert %v to bool", arg) |
393 | } |
394 | return reflect.ValueOf(b), args, nil |
395 | }, nil |
396 | case pt.Kind() == reflect.Slice: |
397 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
398 | converter, err := e.buildConverter(pt.Elem()) |
399 | if err != nil { |
400 | return reflect.Value{}, nil, err |
401 | } |
402 | result := reflect.MakeSlice(reflect.SliceOf(pt.Elem()), 0, len(args)) |
403 | for range args { |
404 | value, remains, err := converter(n, args) |
405 | if err != nil { |
406 | return reflect.Value{}, nil, err |
407 | } |
408 | result = reflect.Append(result, value) |
409 | args = remains |
410 | } |
411 | return result, args, nil |
412 | }, nil |
413 | default: |
414 | if pt.Kind() == reflect.Interface && pt.NumMethod() == 0 { |
415 | return func(n *expect.Note, args []interface{}) (reflect.Value, []interface{}, error) { |
416 | if len(args) < 1 { |
417 | return reflect.Value{}, nil, fmt.Errorf("missing argument") |
418 | } |
419 | return reflect.ValueOf(args[0]), args[1:], nil |
420 | }, nil |
421 | } |
422 | return nil, fmt.Errorf("param has unexpected type %v (kind %v)", pt, pt.Kind()) |
423 | } |
424 | } |
425 | |
426 | func (e *Exported) rangeConverter(n *expect.Note, args []interface{}) (Range, []interface{}, error) { |
427 | tokFile := e.ExpectFileSet.File(n.Pos) |
428 | if len(args) < 1 { |
429 | return Range{}, nil, fmt.Errorf("missing argument") |
430 | } |
431 | arg := args[0] |
432 | args = args[1:] |
433 | switch arg := arg.(type) { |
434 | case expect.Identifier: |
435 | // handle the special identifiers |
436 | switch arg { |
437 | case eofIdentifier: |
438 | // end of file identifier |
439 | eof := tokFile.Pos(tokFile.Size()) |
440 | return newRange(tokFile, eof, eof), args, nil |
441 | default: |
442 | // look up an marker by name |
443 | mark, ok := e.markers[string(arg)] |
444 | if !ok { |
445 | return Range{}, nil, fmt.Errorf("cannot find marker %v", arg) |
446 | } |
447 | return mark, args, nil |
448 | } |
449 | case string: |
450 | start, end, err := expect.MatchBefore(e.ExpectFileSet, e.FileContents, n.Pos, arg) |
451 | if err != nil { |
452 | return Range{}, nil, err |
453 | } |
454 | if !start.IsValid() { |
455 | return Range{}, nil, fmt.Errorf("%v: pattern %s did not match", e.ExpectFileSet.Position(n.Pos), arg) |
456 | } |
457 | return newRange(tokFile, start, end), args, nil |
458 | case *regexp.Regexp: |
459 | start, end, err := expect.MatchBefore(e.ExpectFileSet, e.FileContents, n.Pos, arg) |
460 | if err != nil { |
461 | return Range{}, nil, err |
462 | } |
463 | if !start.IsValid() { |
464 | return Range{}, nil, fmt.Errorf("%v: pattern %s did not match", e.ExpectFileSet.Position(n.Pos), arg) |
465 | } |
466 | return newRange(tokFile, start, end), args, nil |
467 | default: |
468 | return Range{}, nil, fmt.Errorf("cannot convert %v to pos", arg) |
469 | } |
470 | } |
471 | |
472 | // newRange creates a new Range from a token.File and two valid positions within it. |
473 | func newRange(file *token.File, start, end token.Pos) Range { |
474 | fileBase := file.Base() |
475 | fileEnd := fileBase + file.Size() |
476 | if !start.IsValid() { |
477 | panic("invalid start token.Pos") |
478 | } |
479 | if !end.IsValid() { |
480 | panic("invalid end token.Pos") |
481 | } |
482 | if int(start) < fileBase || int(start) > fileEnd { |
483 | panic(fmt.Sprintf("invalid start: %d not in [%d, %d]", start, fileBase, fileEnd)) |
484 | } |
485 | if int(end) < fileBase || int(end) > fileEnd { |
486 | panic(fmt.Sprintf("invalid end: %d not in [%d, %d]", end, fileBase, fileEnd)) |
487 | } |
488 | if start > end { |
489 | panic("invalid start: greater than end") |
490 | } |
491 | return Range{ |
492 | TokFile: file, |
493 | Start: start, |
494 | End: end, |
495 | } |
496 | } |
497 |
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