Using the new watch api of compiler

[sheetalkamat]

This works with the changes of microsoft/TypeScript#20234

[jrieken]

@sheetalkamat Would performance be like that of tsc --watch? That wouldn't be bad tho needs careful validation. My quick perf-test didn't reveal much of a different between them which is good needs. This is what I did

Start compilers, let them start and listen for changes, then:

1. in arrays.ts, line 34, change low to lw to test a local change
2. in arrays.ts, line 33, change binarySearch to binrySearch to test a real shape change
3. in decorationsService.ts change _disposable on line 233 to _dispsable to test a local change

Results (as read from the terminal) are very similar, values are ordered 'tsc vs. tsb':

1. 1 sec vs 770ms, undoing 1sec vs 312ms
2. 5sec vs 4843ms, undoing 4sec vs 3836ms
3. 1sec vs 283ms, undoing 0sec vs 239ms

@sheetalkamat I assume the performance of the new gulp-tsb will be very similar to tsc --watch. That would be good. I can selfhost of tsc for day to get a feel for it. All of this is very good news. Thanks for doing this!

tsc -p src/tsconfig.json --watch

jrieken:~/Code/vscode$ tsc -p src/tsconfig.json --watch
11:40:33 - Compilation complete. Watching for file changes.


11:40:47 - File change detected. Starting incremental compilation...


src/vs/base/common/arrays.ts(34,6): error TS6133: 'lw' is declared but its value is never read.
src/vs/base/common/arrays.ts(37,9): error TS2304: Cannot find name 'low'.
src/vs/base/common/arrays.ts(38,15): error TS2304: Cannot find name 'low'.
src/vs/base/common/arrays.ts(41,4): error TS2304: Cannot find name 'low'.
src/vs/base/common/arrays.ts(48,11): error TS2304: Cannot find name 'low'.
11:40:48 - Compilation complete. Watching for file changes.


11:40:54 - File change detected. Starting incremental compilation...


11:40:55 - Compilation complete. Watching for file changes.


11:41:06 - File change detected. Starting incremental compilation...


src/vs/base/test/common/arrays.test.ts(182,23): error TS2551: Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
src/vs/base/test/common/arrays.test.ts(183,23): error TS2551: Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
src/vs/base/test/common/arrays.test.ts(186,23): error TS2551: Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
src/vs/base/test/common/arrays.test.ts(187,23): error TS2551: Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
src/vs/base/test/common/arrays.test.ts(188,23): error TS2551: Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
src/vs/platform/telemetry/browser/errorTelemetry.ts(8,10): error TS2305: Module '"/Users/jrieken/Code/vscode/src/vs/base/common/arrays"' has no exported member 'binarySearch'.
src/vs/workbench/parts/output/browser/outputServices.ts(9,10): error TS2305: Module '"/Users/jrieken/Code/vscode/src/vs/base/common/arrays"' has no exported member 'binarySearch'.
11:41:11 - Compilation complete. Watching for file changes.


11:41:16 - File change detected. Starting incremental compilation...


11:41:20 - Compilation complete. Watching for file changes.


11:41:31 - File change detected. Starting incremental compilation...


src/vs/workbench/services/decorations/browser/decorationsService.ts(233,19): error TS6133: '_dispable' is declared but its value is never read.
src/vs/workbench/services/decorations/browser/decorationsService.ts(240,8): error TS2551: Property '_dispoable' does not exist on type 'DecorationProviderWrapper'. Did you mean '_dispable'?
src/vs/workbench/services/decorations/browser/decorationsService.ts(256,8): error TS2551: Property '_dispoable' does not exist on type 'DecorationProviderWrapper'. Did you mean '_dispable'?
11:41:31 - Compilation complete. Watching for file changes.


11:41:34 - File change detected. Starting incremental compilation...


11:41:34 - Compilation complete. Watching for file changes.


^C

npm run watch

[11:43:00] Starting 'watch-client'...
[11:44:03] [monaco.d.ts] Starting monaco.d.ts generation
[11:44:06] [monaco.d.ts] Finished monaco.d.ts generation
[11:44:06] Finished compilation with 0 errors after 77678 ms
[11:44:33] Starting compilation...
[11:44:33] Error: /Users/jrieken/Code/vscode/src/vs/base/common/arrays.ts(34,6): 'lw' is declared but its value is never read.
[11:44:33] Error: /Users/jrieken/Code/vscode/src/vs/base/common/arrays.ts(37,9): Cannot find name 'low'.
[11:44:33] Error: /Users/jrieken/Code/vscode/src/vs/base/common/arrays.ts(38,15): Cannot find name 'low'.
[11:44:33] Error: /Users/jrieken/Code/vscode/src/vs/base/common/arrays.ts(41,4): Cannot find name 'low'.
[11:44:33] Error: /Users/jrieken/Code/vscode/src/vs/base/common/arrays.ts(48,11): Cannot find name 'low'.
[11:44:33] Finished compilation with 5 errors after 770 ms
[11:44:37] Starting compilation...
[11:44:37] Finished compilation with 0 errors after 312 ms
[11:44:42] Starting compilation...
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/base/test/common/arrays.test.ts(182,23): Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/base/test/common/arrays.test.ts(183,23): Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/base/test/common/arrays.test.ts(186,23): Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/base/test/common/arrays.test.ts(187,23): Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/base/test/common/arrays.test.ts(188,23): Property 'binarySearch' does not exist on type 'typeof "/Users/jrieken/Code/vscode/src/vs/base/common/arrays"'. Did you mean 'binrySearch'?
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/platform/telemetry/browser/errorTelemetry.ts(8,10): Module '"/Users/jrieken/Code/vscode/src/vs/base/common/arrays"' has no exported member 'binarySearch'.
[11:44:47] Error: /Users/jrieken/Code/vscode/src/vs/workbench/parts/output/browser/outputServices.ts(9,10): Module '"/Users/jrieken/Code/vscode/src/vs/base/common/arrays"' has no exported member 'binarySearch'.
[11:44:47] Finished compilation with 7 errors after 4843 ms
[11:44:51] Starting compilation...
[11:44:55] Finished compilation with 0 errors after 3836 ms
[11:45:12] Starting compilation...
[11:45:12] Error: /Users/jrieken/Code/vscode/src/vs/workbench/services/decorations/browser/decorationsService.ts(233,19): '_dispable' is declared but its value is never read.
[11:45:12] Error: /Users/jrieken/Code/vscode/src/vs/workbench/services/decorations/browser/decorationsService.ts(240,8): Property '_dispoable' does not exist on type 'DecorationProviderWrapper'. Did you mean '_dispable'?
[11:45:12] Error: /Users/jrieken/Code/vscode/src/vs/workbench/services/decorations/browser/decorationsService.ts(256,8): Property '_dispoable' does not exist on type 'DecorationProviderWrapper'. Did you mean '_dispable'?
[11:45:12] Finished compilation with 3 errors after 283 ms
[11:45:15] Starting compilation...
[11:45:15] Finished compilation with 0 errors after 239 ms

[sheetalkamat]

@jrieken Yes this would use the same api to create program and update them as watch does with few changes. tsc -w watches files/directories but I wasn't sure how and what to do about that here since I am not very clear on how and when build is invoked. If you look at https://github.com/jrieken/gulp-tsb/pull/74/files#diff-f8924a760912596517f9ae8931e4f7a5R658 and https://github.com/jrieken/gulp-tsb/pull/74/files#diff-f8924a760912596517f9ae8931e4f7a5R662 the implementations currently just keep track of files/directories watched instead of using ts.sys.watchFile/ts.sys.watchDirectory. I wasn't sure what to do about that and wasn't sure if caller of the build is watching those files/directories or not.

[jrieken]

@sheetalkamat Against what version of TS will this run? Is this TS 2.6.x, 2.7, or still to be defined?

[sheetalkamat]

@jrieken this runs against branch from microsoft/TypeScript#20234 which is yet to be merged.

[sheetalkamat]

Closing this in favor of #76