-
Notifications
You must be signed in to change notification settings - Fork 48
/
racer.el
925 lines (833 loc) · 34.2 KB
/
racer.el
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
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
;;; racer.el --- code completion, goto-definition and docs browsing for Rust via racer -*- lexical-binding: t -*-
;; Copyright (c) 2014 Phil Dawes
;; Author: Phil Dawes
;; URL: https://github.com/racer-rust/emacs-racer
;; Version: 1.3
;; Package-Requires: ((emacs "25.1") (rust-mode "0.2.0") (dash "2.13.0") (s "1.10.0") (f "0.18.2") (pos-tip "0.4.6"))
;; Keywords: abbrev, convenience, matching, rust, tools
;; This file is not part of GNU Emacs.
;; Permission is hereby granted, free of charge, to any
;; person obtaining a copy of this software and associated
;; documentation files (the "Software"), to deal in the
;; Software without restriction, including without
;; limitation the rights to use, copy, modify, merge,
;; publish, distribute, sublicense, and/or sell copies of
;; the Software, and to permit persons to whom the Software
;; is furnished to do so, subject to the following
;; conditions:
;; The above copyright notice and this permission notice
;; shall be included in all copies or substantial portions
;; of the Software.
;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
;; ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
;; TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
;; PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
;; SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
;; CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
;; OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
;; IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
;; DEALINGS IN THE SOFTWARE.
;;; Commentary:
;; Please see the readme for full documentation:
;; https://github.com/racer-rust/emacs-racer
;;; Quickstart:
;; You will need to configure Emacs to find racer:
;;
;; (setq racer-rust-src-path "<path-to-rust-srcdir>/src/")
;; (setq racer-cmd "<path-to-racer>/target/release/racer")
;;
;; To activate racer in Rust buffers, run:
;;
;; (add-hook 'rust-mode-hook #'racer-mode)
;;
;; You can also use racer to find definition at point via
;; `racer-find-definition', bound to `M-.' by default.
;;
;; Finally, you can also use Racer to show the signature of the
;; current function in the minibuffer:
;;
;; (add-hook 'racer-mode-hook #'eldoc-mode)
;;; Code:
(require 'dash)
(require 'etags)
(require 'rust-mode)
(require 's)
(require 'f)
(require 'thingatpt)
(require 'button)
(require 'help-mode)
(autoload 'pos-tip-show-no-propertize "pos-tip")
(defgroup racer nil
"Code completion, goto-definition and docs browsing for Rust via racer."
:link '(url-link "https://github.com/racer-rust/emacs-racer/")
:group 'rust-mode)
(defcustom racer-cmd
(or (executable-find "racer")
(f-expand "~/.cargo/bin/racer")
"/usr/local/bin/racer")
"Path to the racer binary."
:type 'file
:group 'racer)
(defcustom racer-rust-src-path
(or
(getenv "RUST_SRC_PATH")
(when (executable-find "rustc")
(let* ((sysroot (s-trim-right
(shell-command-to-string
(format "%s --print sysroot" (executable-find "rustc")))))
(lib-path (f-join sysroot "lib/rustlib/src/rust/library"))
(src-path (f-join sysroot "lib/rustlib/src/rust/src")))
(or (when (file-exists-p lib-path) lib-path)
(when (file-exists-p src-path) src-path))))
"/usr/local/src/rust/src")
"Path to the rust source tree.
If nil, we will query $RUST_SRC_PATH at runtime.
If $RUST_SRC_PATH is not set, look for rust source in rustup's install directory."
:type 'file
:group 'racer)
(defcustom racer-cargo-home
(or
(getenv "CARGO_HOME")
"~/.cargo")
"Path to your current cargo home. Usually `~/.cargo'.
If nil, we will query $CARGO_HOME at runtime."
:type 'file
:group 'racer)
(defun racer--cargo-project-root ()
"Find the root of the current Cargo project."
(let ((root (locate-dominating-file (or (buffer-file-name (buffer-base-buffer)) default-directory)
"Cargo.toml")))
(and root (file-truename root))))
(defun racer--header (text)
"Helper function for adding text properties to TEXT."
(propertize text 'face 'racer-help-heading-face))
(defvar racer--prev-state nil)
(defun racer-debug ()
"Open a buffer describing the last racer command run.
Helps users find configuration issues, or file bugs on
racer or racer.el."
(interactive)
(unless racer--prev-state
(user-error "Must run a racer command before debugging"))
(let ((buf (get-buffer-create "*racer-debug*"))
(inhibit-read-only t))
(with-current-buffer buf
(erase-buffer)
(setq buffer-read-only t)
(let* ((process-environment
(plist-get racer--prev-state :process-environment))
(rust-src-path-used
(--first (s-prefix-p "RUST_SRC_PATH=" it) process-environment))
(cargo-home-used
(--first (s-prefix-p "CARGO_HOME=" it) process-environment))
(stdout (plist-get racer--prev-state :stdout))
(stderr (plist-get racer--prev-state :stderr)))
(insert
;; Summarise the actual command that we run.
(racer--header "The last racer command was:\n\n")
(format "$ cd %s\n"
(plist-get racer--prev-state :default-directory))
(format "$ export %s\n" cargo-home-used)
(format "$ export %s\n" rust-src-path-used)
(format "$ %s %s\n\n"
(plist-get racer--prev-state :program)
(s-join " " (plist-get racer--prev-state :args)))
;; Describe the exit code and outputs.
(racer--header
(format "This command terminated with exit code %s.\n\n"
(plist-get racer--prev-state :exit-code)))
(if (s-blank? stdout)
(racer--header "No output on stdout.\n\n")
(format "%s\n\n%s\n\n"
(racer--header "stdout:")
(s-trim-right stdout)))
(if (s-blank? stderr)
(racer--header "No output on stderr.\n\n")
(format "%s\n\n%s\n\n"
(racer--header "stderr:")
(s-trim-right stderr)))
;; Give copy-paste instructions for reproducing any errors
;; the user has seen.
(racer--header
(s-word-wrap 60 "The temporary file will have been deleted. You should be able to reproduce the same output from racer with the following command:\n\n"))
(format "$ %s %s %s %s\n\n" cargo-home-used rust-src-path-used
(plist-get racer--prev-state :program)
(s-join " "
(-drop-last 1 (plist-get racer--prev-state :args))))
;; Tell the user what to do next if they have problems.
(racer--header "Please report bugs ")
(racer--url-button "on GitHub" "https://github.com/racer-rust/emacs-racer/issues/new")
(racer--header "."))))
(switch-to-buffer buf)
(goto-char (point-min))))
(defun racer--call (command &rest args)
"Call racer command COMMAND with args ARGS.
Return stdout if COMMAND exits normally, otherwise show an
error."
(let ((rust-src-path (or (when racer-rust-src-path (expand-file-name racer-rust-src-path))
(getenv "RUST_SRC_PATH")))
(cargo-home (or (when racer-cargo-home (expand-file-name racer-cargo-home))
(getenv "CARGO_HOME"))))
(when (null rust-src-path)
(user-error "You need to set `racer-rust-src-path' or `RUST_SRC_PATH'"))
(unless (file-exists-p rust-src-path)
(user-error "No such directory: %s. Please set `racer-rust-src-path' or `RUST_SRC_PATH'"
rust-src-path))
(let ((default-directory (or (racer--cargo-project-root) default-directory))
(process-environment (append (list
(format "RUST_SRC_PATH=%s" rust-src-path)
(format "CARGO_HOME=%s" cargo-home))
process-environment)))
(-let [(exit-code stdout _stderr)
(racer--shell-command racer-cmd (cons command args))]
;; Use `equal' instead of `zero' as exit-code can be a string
;; "Aborted" if racer crashes.
(unless (equal 0 exit-code)
(user-error "%s exited with %s. `M-x racer-debug' for more info"
racer-cmd exit-code))
stdout))))
(defmacro racer--with-temporary-file (path-sym &rest body)
"Create a temporary file, and bind its path to PATH-SYM.
Evaluate BODY, then delete the temporary file."
(declare (indent 1) (debug (symbolp body)))
`(let ((,path-sym (make-temp-file "racer")))
(unwind-protect
(progn ,@body)
(delete-file ,path-sym))))
(defmacro racer--with-temp-buffers (stdout-sym stderr-sym &rest body)
(declare (indent 2) (debug (symbolp body)))
`(let ((kill-buffer-query-functions nil)
(,stdout-sym (generate-new-buffer " *racer-stdout*"))
(,stderr-sym (generate-new-buffer " *racer-stderr*")))
(unwind-protect
(progn ,@body)
(when (buffer-name ,stdout-sym)
(kill-buffer ,stdout-sym))
(when (buffer-name ,stderr-sym)
(kill-buffer ,stderr-sym)))))
(defcustom racer-command-timeout nil
"Abandon completion if racer process fails to respond for that
many seconds (maybe float). nil means wait indefinitely."
:type 'number
:group 'racer)
(defun racer--shell-command (program args)
"Execute PROGRAM with ARGS. Return a list (exit-code stdout
stderr)."
(racer--with-temp-buffers stdout stderr
(let (exit-code
stdout-result
stderr-result
(proc (make-process :name "*async-racer*"
:buffer stdout
:command (cons program args)
:connection-type 'pipe
:stderr stderr)))
(while
(and (process-live-p proc)
(with-local-quit
(accept-process-output proc racer-command-timeout))))
(when (process-live-p proc) (kill-process proc))
(setq exit-code (process-exit-status proc)
stderr-result (with-current-buffer stderr (buffer-string))
stdout-result (with-current-buffer stdout (buffer-string)))
(setq racer--prev-state
(list
:program program
:args args
:exit-code exit-code
:stdout stdout-result
:stderr stderr-result
:default-directory default-directory
:process-environment process-environment))
(list exit-code stdout-result stderr-result))))
(defun racer--call-at-point (command)
"Call racer command COMMAND at point of current buffer.
Return a list of all the lines returned by the command."
(racer--with-temporary-file tmp-file
(write-region nil nil tmp-file nil 'silent)
(let ((racer-args (list
command
(number-to-string (line-number-at-pos))
(number-to-string (racer--current-column)))))
;; If this buffer is backed by a file, pass that to racer too.
(-when-let (file-name (buffer-file-name (buffer-base-buffer)))
(setq racer-args
(append racer-args (list file-name))))
(setq racer-args (append racer-args (list tmp-file)))
(s-lines
(s-trim-right
(apply #'racer--call racer-args))))))
(defun racer--read-rust-string (string)
"Convert STRING, a rust string literal, to an elisp string."
(when string
;; Remove outer double quotes.
(setq string (s-chop-prefix "\"" string))
(setq string (s-chop-suffix "\"" string))
;; Translate escape sequences.
(replace-regexp-in-string
(rx "\\" (group anything))
(lambda (whole-match)
(let ((escaped-char (match-string 1 whole-match)))
(if (equal escaped-char "n")
"\n"
escaped-char)))
string
t t)))
(defun racer--split-parts (raw-output)
"Given RAW-OUTPUT from racer, split on semicolons and doublequotes.
Unescape strings as necessary."
(let ((parts nil)
(current "")
(i 0))
(while (< i (length raw-output))
(let ((char (elt raw-output i))
(prev-char (and (> i 0) (elt raw-output (1- i)))))
(cond
;; A semicolon that wasn't escaped, start a new part.
((and (equal char ?\;) (not (equal prev-char ?\\)))
(push current parts)
(setq current ""))
(t
(setq current (concat current (string char))))))
(setq i (1+ i)))
(push current parts)
(mapcar #'racer--read-rust-string (nreverse parts))))
(defun racer--split-snippet-match (line)
"Given LINE, a string \"MATCH ...\" from complete-with-snippet,
split it into its constituent parts."
(let* ((match-parts (racer--split-parts line))
(docstring (nth 7 match-parts)))
(when (and match-parts (equal (length match-parts) 8))
(list :name (s-chop-prefix "MATCH " (nth 0 match-parts))
:line (string-to-number (nth 2 match-parts))
:column (string-to-number (nth 3 match-parts))
:path (nth 4 match-parts)
;; Struct or Function:
:kind (nth 5 match-parts)
:signature (nth 6 match-parts)
:docstring (if (> (length docstring) 0) docstring nil)))))
(defun racer--order-descriptions (descriptions)
(sort descriptions
(lambda (a b)
(let ((a (or (plist-get a :docstring) ""))
(b (or (plist-get b :docstring) "")))
(> (length a) (length b))))))
(defun racer--describe-at-point (name)
"Get a descriptions of the symbols matching symbol at point and
NAME. If there are multiple possibilities with this NAME, prompt
the user to choose. Return a list of all possibilities that
start with the user's selection."
(let* ((output-lines (save-excursion
;; Move to the end of the current symbol, to
;; increase racer accuracy.
(skip-syntax-forward "w_")
(racer--call-at-point "complete-with-snippet")))
(all-matches (--map (when (s-starts-with-p "MATCH " it)
(racer--split-snippet-match it))
output-lines))
(relevant-matches (--filter (equal (plist-get it :name) name)
all-matches)))
(racer--order-descriptions
(if (> (length relevant-matches) 1)
;; We might have multiple matches with the same name but
;; different types. E.g. Vec::from.
(let ((signature
(completing-read "Multiple matches: "
(--map (plist-get it :signature) relevant-matches))))
(-filter
(lambda (x)
(let ((sig (plist-get x :signature)))
(equal (substring sig 0 (min (length sig) (length signature)))
signature)))
relevant-matches))
relevant-matches))))
(defun racer--help-buf (contents)
"Create a *Racer Help* buffer with CONTENTS."
(let ((buf (get-buffer-create "*Racer Help*"))
;; If the buffer already existed, we need to be able to
;; override `buffer-read-only'.
(inhibit-read-only t))
(with-current-buffer buf
(erase-buffer)
(insert contents)
(setq buffer-read-only t)
(goto-char (point-min))
(racer-help-mode))
buf))
(defface racer-help-heading-face
'((t :weight bold))
"Face for markdown headings in *Racer Help* buffers.")
(defun racer--url-p (target)
"Return t if TARGET looks like a fully qualified URL."
(not (null
(string-match-p (rx bol "http" (? "s") ":https://") target))))
(defun racer--propertize-links (markdown)
"Propertize links in MARKDOWN."
(replace-regexp-in-string
;; Text of the form [foo](https://example.com)
(rx "[" (group (+? (not (any "]")))) "](" (group (+? anything)) ")")
;; For every match:
(lambda (whole-match)
;; Extract link and target.
(let ((link-text (match-string 1 whole-match))
(link-target (match-string 2 whole-match)))
;; If it's a web URL, use a clickable link.
(if (racer--url-p link-target)
(racer--url-button link-text link-target)
;; Otherwise, just discard the target.
link-text)))
markdown
t t))
(defun racer--propertize-all-inline-code (markdown)
"Given a single line MARKDOWN, replace all instances of `foo` or
\[`foo`\] with a propertized string."
(let ((highlight-group
(lambda (whole-match)
(racer--syntax-highlight (match-string 1 whole-match)))))
(setq markdown
(replace-regexp-in-string
(rx "[`" (group (+? anything)) "`]")
highlight-group
markdown
t t))
(setq markdown
(replace-regexp-in-string
(rx "`" (group (+? anything)) "`")
highlight-group
markdown
t t))))
(defun racer--indent-block (str)
"Indent every line in STR."
(s-join "\n" (--map (concat " " it) (s-lines str))))
(defun racer--trim-newlines (str)
"Remove newlines from the start and end of STR."
(->> str
(s-chop-prefix "\n")
(s-chop-suffix "\n")))
(defun racer--remove-footnote-links (str)
"Remove footnote links from markdown STR."
(->> (s-lines str)
(--remove (string-match-p (rx bol "[`" (+? anything) "`]: ") it))
(s-join "\n")
;; Collapse consecutive blank lines caused by removing footnotes.
(s-replace "\n\n\n" "\n\n")))
(defun racer--docstring-sections (docstring)
"Split DOCSTRING into text, code and heading sections."
(let* ((sections nil)
(current-section-lines nil)
(section-type :text)
;; Helper function.
(finish-current-section
(lambda ()
(when current-section-lines
(let ((current-section
(s-join "\n" (nreverse current-section-lines))))
(unless (s-blank? current-section)
(push (list section-type current-section) sections))
(setq current-section-lines nil))))))
(dolist (line (s-lines docstring))
(cond
;; If this is a closing ```
((and (s-starts-with-p "```" line) (eq section-type :code))
(push line current-section-lines)
(funcall finish-current-section)
(setq section-type :text))
;; If this is an opening ```
((s-starts-with-p "```" line)
(funcall finish-current-section)
(push line current-section-lines)
(setq section-type :code))
;; Headings
((and (not (eq section-type :code)) (s-starts-with-p "# " line))
(funcall finish-current-section)
(push (list :heading line) sections))
;; Normal text.
(t
(push line current-section-lines))))
(funcall finish-current-section)
(nreverse sections)))
(defun racer--clean-code-section (section)
"Given a SECTION, a markdown code block, remove
fenced code delimiters and code annotations."
(->> (s-lines section)
(-drop 1)
(-drop-last 1)
;; Ignore annotations like # #[allow(dead_code)]
(--remove (s-starts-with-p "# " it))
(s-join "\n")))
(defun racer--propertize-docstring (docstring)
"Replace markdown syntax in DOCSTRING with text properties."
(let* ((sections (racer--docstring-sections docstring))
(propertized-sections
(--map (-let [(section-type section) it]
;; Remove trailing newlines, so we can ensure we
;; have consistent blank lines between sections.
(racer--trim-newlines
(pcase section-type
(:text
(racer--propertize-all-inline-code
(racer--propertize-links
(racer--remove-footnote-links
section))))
(:code
(racer--indent-block
(racer--syntax-highlight
(racer--clean-code-section section))))
(:heading
(racer--header
(s-chop-prefix "# " section))))))
sections)))
(s-join "\n\n" propertized-sections)))
(defun racer--find-file (path line column find-file-func)
"Open PATH and move point to LINE and COLUMN."
(funcall find-file-func path)
(goto-char (point-min))
(forward-line (1- line))
(forward-char column))
(defun racer--button-go-to-src (button)
(racer--find-file
(button-get button 'path)
(button-get button 'line)
(button-get button 'column)
#'find-file))
(define-button-type 'racer-src-button
'action 'racer--button-go-to-src
'follow-link t
'help-echo "Go to definition")
(defun racer--url-button (text url)
"Return a button that opens a browser at URL."
(with-temp-buffer
(insert-text-button
text
:type 'help-url
'help-args (list url))
(buffer-string)))
(defun racer--src-button (path line column)
"Return a button that navigates to PATH at LINE number and
COLUMN number."
;; Convert "/foo/bar/baz/foo.rs" to "baz/foo.rs"
(let* ((filename (f-filename path))
(parent-dir (f-filename (f-parent path)))
(short-path (f-join parent-dir filename)))
(with-temp-buffer
(insert-text-button
short-path
:type 'racer-src-button
'path path
'line line
'column column)
(buffer-string))))
(defun racer--kind-description (raw-kind)
"Human friendly description of a rust kind.
For example, 'EnumKind' -> 'an enum kind'."
(let* ((parts (s-split-words raw-kind))
(description (s-join " " (--map (downcase it) parts)))
(a (if (string-match-p (rx bos (or "a" "e" "i" "o" "u")) description)
"an" "a")))
(format "%s %s" a description)))
(defun racer--describe (name)
"Return a *Racer Help* buffer for the function or type at point.
If there are multiple candidates at point, use NAME to find the
correct value."
(let ((descriptions (racer--describe-at-point name)))
(when descriptions
(racer--help-buf
(let ((output "")
(first-iteration t))
(dolist (description descriptions output)
(unless first-iteration
(setf output
(concat output (format "\n---------------------------------------------------------------\n"))))
(setf output
(concat
output
(let* ((name (plist-get description :name))
(raw-docstring (plist-get description :docstring))
(docstring (if raw-docstring
(racer--propertize-docstring raw-docstring)
"Not documented."))
(kind (plist-get description :kind)))
(setf first-iteration nil)
(format
"%s is %s defined in %s.\n\n%s%s"
name
(racer--kind-description kind)
(racer--src-button
(plist-get description :path)
(plist-get description :line)
(plist-get description :column))
(if (equal kind "Module")
;; No point showing the 'signature' of modules, which is
;; just their full path.
""
(format " %s\n\n" (racer--syntax-highlight (plist-get description :signature))))
docstring))))))))))
(defun racer-describe ()
"Show a *Racer Help* buffer for the function or type at point."
(interactive)
(let ((buf (racer--describe (thing-at-point 'symbol))))
(if buf
(temp-buffer-window-show buf)
(user-error "No function or type found at point"))))
(defface racer-tooltip
'((((min-colors 16777216))
:background "#292C33" :foreground "white")
(t
:background "black" :foreground "white"))
"Face used for the tooltip with `racer-describe-tooltip'")
(defun racer-describe-tooltip ()
"Show the docstring in a tooltip.
The tooltip's face is `racer-tooltip'
See `racer-describe'."
(interactive)
(-some-> (symbol-at-point)
(symbol-name)
(racer--describe)
(with-current-buffer (concat "\n" (buffer-string) "\n\n"))
(pos-tip-show-no-propertize 'racer-tooltip nil nil 1000)))
(defvar racer-help-mode-map
(let ((map (make-sparse-keymap)))
(set-keymap-parent map (make-composed-keymap button-buffer-map
special-mode-map))
map)
"Keymap for racer help mode.")
(define-derived-mode racer-help-mode fundamental-mode
"Racer-Help"
"Major mode for *Racer Help* buffers.
Commands:
\\{racer-help-mode-map}")
(defcustom racer-complete-in-comments
nil
"If non-nil, query racer for completions inside comments too."
:type 'boolean
:group 'racer)
(defcustom racer-complete-insert-argument-placeholders
t
"If non-nil, insert argument placeholders after completion.
Note that this feature is only available when `company-mode' is installed."
:type 'boolean
:group 'racer)
(defun racer-complete-at-point ()
"Complete the symbol at point."
(let* ((ppss (syntax-ppss))
(in-string (nth 3 ppss))
(in-comment (nth 4 ppss)))
(when (and
(not in-string)
(or (not in-comment) racer-complete-in-comments))
(let* ((bounds (bounds-of-thing-at-point 'symbol))
(beg (or (car bounds) (point)))
(end (or (cdr bounds) (point))))
(list beg end
(completion-table-dynamic #'racer-complete)
:annotation-function #'racer-complete--annotation
:company-prefix-length (racer-complete--prefix-p beg end)
:company-docsig #'racer-complete--docsig
:company-doc-buffer #'racer--describe
:company-location #'racer-complete--location
:exit-function #'racer-complete--insert-args)))))
(declare-function company-template-c-like-templatify 'company-template)
(defun racer-complete--insert-args (arg &optional _finished)
"If a ARG is the name of a completed function, try to find and insert its arguments."
(when (and racer-complete-insert-argument-placeholders
(require 'company-template nil t)
(equal "Function"
(get-text-property 0 'matchtype arg))
;; Don't add arguments if the user has already added
;; some.
(not (eq (char-after) ?\()))
(let* ((ctx (get-text-property 0 'ctx arg))
(arguments (racer-complete--extract-args ctx)))
(insert arguments)
(company-template-c-like-templatify arguments))))
(defun racer-complete--extract-args (str)
"Extract function arguments from STR (excluding a possible self argument)."
(string-match
(rx
(or (seq "(" (zero-or-more (not (any ","))) "self)")
(seq "("
(zero-or-more (seq (zero-or-more (not (any "(")))
"self"
(zero-or-more space)
","))
(zero-or-more space)
(group (zero-or-more (not (any ")"))))
")")))
str)
(let ((extract (match-string 1 str)))
(if extract
(format "(%s)" extract)
"()")))
(defun racer--file-and-parent (path)
"Convert /foo/bar/baz/q.txt to baz/q.txt."
(let ((file (f-filename path))
(parent (f-filename (f-parent path))))
(f-join parent file)))
(defun racer-complete (&optional _ignore)
"Completion candidates at point."
(->> (racer--call-at-point "complete")
(--filter (s-starts-with? "MATCH" it))
(--map (-let [(name line col file matchtype ctx)
(s-split-up-to "," (s-chop-prefix "MATCH " it) 5)]
(put-text-property 0 1 'line (string-to-number line) name)
(put-text-property 0 1 'col (string-to-number col) name)
(put-text-property 0 1 'file file name)
(put-text-property 0 1 'matchtype matchtype name)
(put-text-property 0 1 'ctx ctx name)
name))))
(defun racer--trim-up-to (needle s)
"Return content after the occurrence of NEEDLE in S."
(-if-let (idx (s-index-of needle s))
(substring s (+ idx (length needle)))
s))
(defun racer-complete--prefix-p (beg _end)
"Return t if a completion should be triggered for a prefix between BEG and END."
(save-excursion
(goto-char beg)
;; If we're at the beginning of the buffer, we can't look back 2
;; characters.
(ignore-errors
(looking-back "\\.\\|::" 2))))
(defun racer-complete--annotation (arg)
"Return an annotation for completion candidate ARG."
(let* ((ctx (get-text-property 0 'ctx arg))
(type (get-text-property 0 'matchtype arg))
(pretty-ctx
(pcase type
("Module"
(if (string= arg ctx)
""
(concat " " (racer--file-and-parent ctx))))
("StructField"
(concat " " ctx))
(_
(->> ctx
(racer--trim-up-to arg)
(s-chop-suffixes '(" {" "," ";")))))))
(format "%s : %s" pretty-ctx type)))
(defun racer-complete--docsig (arg)
"Return a signature for completion candidate ARG."
(racer--syntax-highlight (format "%s" (get-text-property 0 'ctx arg))))
(defun racer-complete--location (arg)
"Return location of completion candidate ARG."
(cons (get-text-property 0 'file arg)
(get-text-property 0 'line arg)))
(defun racer--current-column ()
"Get the current column based on underlying character representation."
(length (buffer-substring-no-properties
(line-beginning-position) (point))))
(defun racer--find-definition(find-file-func)
(-if-let (match (--first (s-starts-with? "MATCH" it)
(racer--call-at-point "find-definition")))
(-let [(_name line col file _matchtype _ctx)
(s-split-up-to "," (s-chop-prefix "MATCH " match) 5)]
(if (fboundp 'xref-push-marker-stack)
(xref-push-marker-stack)
(with-no-warnings
(ring-insert find-tag-marker-ring (point-marker))))
(racer--find-file file (string-to-number line) (string-to-number col) find-file-func))
(error "No definition found")))
;;;###autoload
(defun racer-find-definition ()
"Run the racer find-definition command and process the results."
(interactive)
(racer--find-definition #'find-file))
;;;###autoload
(defun racer-find-definition-other-window ()
"Run the racer find-definition command and process the results."
(interactive)
(racer--find-definition #'find-file-other-window))
;;;###autoload
(defun racer-find-definition-other-frame ()
"Run the racer find-definition command and process the results."
(interactive)
(racer--find-definition #'find-file-other-frame))
(defun racer--syntax-highlight (str)
"Apply font-lock properties to a string STR of Rust code."
(let (result)
;; Load all of STR in a rust-mode buffer, and use its
;; highlighting.
(save-match-data
(with-temp-buffer
(insert str)
(delay-mode-hooks (rust-mode))
(if (fboundp 'font-lock-ensure)
(font-lock-ensure)
(with-no-warnings
(font-lock-fontify-buffer)))
(setq result (buffer-string))))
;; If we haven't applied any text properties yet, apply some
;; heuristics to try to find an appropriate colour.
(when (null (text-properties-at 0 result))
(cond
;; If it's a standalone symbol, then assume it's a
;; variable.
((string-match-p (rx bos (+ (any lower "_")) eos) str)
(setq result (propertize str 'face 'font-lock-variable-name-face)))
;; If it starts with a backslash, treat it as a string. See
;; .lines() on strings.
((string-match-p (rx bos "\\") str)
(setq result (propertize str 'face 'font-lock-string-face)))))
result))
(defun racer--goto-func-name ()
"If point is inside a function call, move to the function name.
foo(bar, |baz); -> foo|(bar, baz);"
(let ((last-paren-pos (nth 1 (syntax-ppss)))
(start-pos (point)))
(when last-paren-pos
;; Move to just before the last paren.
(goto-char last-paren-pos)
;; If we're inside a round paren, we're inside a function call.
(unless (looking-at "(")
;; Otherwise, return to our start position, as point may have been on a
;; function already:
;; foo|(bar, baz);
(goto-char start-pos)))))
(defun racer--relative (path &optional directory)
"Return PATH relative to DIRECTORY (`default-directory' by default).
If PATH is not in DIRECTORY, just abbreviate it."
(unless directory
(setq directory default-directory))
(if (s-starts-with? directory path)
(concat "./" (f-relative path directory))
(f-abbrev path)))
(defcustom racer-eldoc-timeout 0.5
"Abandon Eldoc hinting if racer process fails to respond for
that many seconds (maybe float)."
:type 'number
:group 'racer)
(defun racer-eldoc ()
"Show eldoc for context at point."
(save-excursion
(racer--goto-func-name)
;; If there's a variable at point:
(-when-let* ((rust-sym (symbol-at-point))
(comp-possibilities (let ((racer-command-timeout racer-eldoc-timeout))
(racer-complete)))
(matching-possibility
(--find (string= it (symbol-name rust-sym)) comp-possibilities))
(prototype (get-text-property 0 'ctx matching-possibility))
(matchtype (get-text-property 0 'matchtype matching-possibility)))
(if (equal matchtype "Module")
(racer--relative prototype)
;; Syntax highlight function signatures.
(racer--syntax-highlight prototype)))))
(defvar racer-mode-map
(let ((map (make-sparse-keymap)))
(define-key map (kbd "M-.") #'racer-find-definition)
(define-key map (kbd "C-x 4 .") #'racer-find-definition-other-window)
(define-key map (kbd "C-x 5 .") #'racer-find-definition-other-frame)
(define-key map (kbd "M-,") #'pop-tag-mark)
map))
;;;###autoload
(define-minor-mode racer-mode
"Minor mode for racer."
:lighter " racer"
:keymap racer-mode-map
(setq-local eldoc-documentation-function #'racer-eldoc)
(set (make-local-variable 'completion-at-point-functions) nil)
(add-hook 'completion-at-point-functions #'racer-complete-at-point))
(define-obsolete-function-alias 'racer-turn-on-eldoc 'eldoc-mode "2015-08-24")
(define-obsolete-function-alias 'racer-activate 'racer-mode "2015-08-24")
(provide 'racer)
;;; racer.el ends here