misc nim js

[timotheecour]

• D20200408T182006 headless mode test code that requires a browser (ie nim js without -d:nodejs)
  eg: Add module jsfetch nim-lang/Nim#12531 (comment)

links

https://developers.google.com/web/updates/2017/06/headless-karma-mocha-chai
https://developers.google.com/web/updates/2017/04/headless-chrome
cheerp: Cheerp | C/C++ to WebAssembly compiler

[timotheecour]

js target should use jstring everywhere instead of cstring; but we can introduce an alias type cstring = jstring

[timotheecour]

nim js -r -d:nimbrowser main should open simple html template that includes generated js in a browser
(analog to karun)
D20200405T220907

EDIT: could be via:
nim js -r --port:1234 -d:nimbrowser main

[timotheecour]

• D20200408T181926 runnableExamples for js code (for -d:nimjsbrowser) should be runnable in browser in generated docs from nim doc
  see also D20200408T182006 and D20200405T220907 (which are different though)

[timotheecour]

• D20200408T183728
  nim js should preserve style eg:

when defined case5:
  proc fooBar() =
    var barBaz = 1
    echo barBaz
  fooBar()

generates:

function foo_bar_13797801() {
    var bar_baz_13797804 = 1;
    rawEcho(cstrToNimstr((bar_baz_13797804)+""));

  
}
foo_bar_13797801();

=> should be fooBar_13797801 not foo_bar_13797801 etc (makes things easier to search, more consistent etc; plus we already have things like function cstrToNimstr( anyways

[timotheecour]

enhance openDefaultBrowser: option to open in new window (not new tab)
see D20200408T185200

[timotheecour]

nim-lang#13974 (comment)

but for nim doc -r main it should be as simple as opening the browser

[timotheecour]

Add Optional JavaScript 'let' variables by juancarlospaco · Pull Request #13851 · nim-lang/Nim : Add Optional JavaScript 'let' variables by juancarlospaco · Pull Request #13851 · nim-lang/Nim
=> closed

[timotheecour]

• I fixed it in a recent PR
  js stacktrace messed up, eg: doesn't show full paths:

$nimb js -r --excessivestacktrace $nim_prs_D/tests/system/tostring.nim
("bee", 3)
("bee", 3)
047FC620
0x10488fd08
(x1: 1, x2: 0x0, x3: @[nil, 0x10488fd08, 0x104892208], x4: 0x10488fd08)
Hint: 44960 LOC; 0.324 sec; 49.844MiB peakmem; Debug build; proj: tostring; out: tostring.js [SuccessX]
("bee", 3)
("bee\x00", 4)
/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:581
    throw new Error(cbuf_3715201);
    ^

Error: Error: unhandled exception: /Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.nim(102, 12) `g == "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"`  [AssertionError]
Traceback (most recent call last)
tostring.stringCompare, line: 102
assertions.failedAssertImpl, line: 29
assertions.raiseAssert, line: 22
sysFatal.sysFatal, line: 49

    at unhandledException (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:581:11)
    at raiseException (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:319:5)
    at sys_fatal_3627618 (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:594:5)
    at raise_assert_3627614 (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:603:5)
    at failed_assert_impl_3627680 (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:612:5)
    at string_compare_13475214 (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:1743:5)
    at Object.<anonymous> (/Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js:2148:1)
    at Module._compile (internal/modules/cjs/loader.js:1147:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1167:10)
    at Module.load (internal/modules/cjs/loader.js:996:32)
Error: execution of an external program failed: '/usr/local/Cellar/node/13.12.0/bin/node /Users/timothee/git_clone/nim/Nim_prs/tests/system/tostring.js '
No stack traceback available
To create a stacktrace, rerun compilation with ./koch temp js <file>

[timotheecour]

testament/testament --targets:js --nim:$nimb r tests/js/trefbyvar.nim doesn't work
(eg when file doesn't specify a target entry)

also, why is c appended to targets:

testament/testament --nim:$nimb r tests/js/trefbyvar.nim
gtk+3 3.24.14
PASS: tests/js/trefbyvar.nim C                                     ( 0.48 sec)
PASS: tests/js/trefbyvar.nim JS                                    ( 0.74 sec)
Used bin/nim.pr_dollar_ptr to run the tests. Use --nim to override.

=> nim-lang#14242

[timotheecour]

test all importjs automatically to make sure they're correct (avoiding errors like #87 (comment))

[timotheecour]

introduce jstring and remap cstring to Uint8Array
see cstring implicit conversion to pointer broken on JS · Issue #14097 · nim-lang/Nim

[timotheecour]

• add: === to jsffi

refs: nim-lang#16409 (comment)

proc `===`[T1, T2](a: T1, b: T2): bool {.importjs: "# === #.}`