[llvm] [lit] Add stream-injectable run() core to builtin diff (PR #204869)

[via llvm-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Linux-->
# :penguin: Linux x64 Test Results

* 176063 tests passed
* 3515 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### lit
<details>
<summary>lit.lit/shtest-shell.py</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 3
not env -u FILECHECK_OPTS "/usr/bin/python3" /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/utils/lit/lit.py -j1 -D use_normalized_slashes=0 --order=lexical -v Inputs/shtest-shell > /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Output/shtest-shell.py.tmp.out
# executed command: not env -u FILECHECK_OPTS /usr/bin/python3 /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/utils/lit/lit.py -j1 -D use_normalized_slashes=0 --order=lexical -v Inputs/shtest-shell
# note: command had no output on stdout or stderr
# RUN: at line 4
FileCheck --input-file /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Output/shtest-shell.py.tmp.out /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/shtest-shell.py
# executed command: FileCheck --input-file /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Output/shtest-shell.py.tmp.out /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/shtest-shell.py
# .---command stderr------------
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/shtest-shell.py:468:10: error: CHECK: expected string not found in input
# | # CHECK: # | Error: invalid '-U' argument: 30.1
# |          ^
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Output/shtest-shell.py.tmp.out:831:33: note: scanning from here
# | # .---command stderr------------
# |                                 ^
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Output/shtest-shell.py.tmp.out:847:15: note: possible intended match here
# | # | stderr.write("Error: invalid '-U' argument: {}\n".format(a))
# |               ^
# | 
# | Input file: /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Output/shtest-shell.py.tmp.out
# | Check file: /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/shtest-shell.py
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |              .
# |              .
# |              .
# |            826: # error: command failed with exit status: 1 
# |            827: # executed command: true 
# |            828: # RUN: at line 34 
# |            829: diff -U 30.1 /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Inputs/shtest-shell/Output/diff-unified.txt.tmp.foo /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Inputs/shtest-shell/Output/diff-unified.txt.tmp.foo && false || true 
# |            830: # executed command: diff -U 30.1 /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Inputs/shtest-shell/Output/diff-unified.txt.tmp.foo /home/gha/actions-runner/_work/llvm-project/llvm-project/build/utils/lit/tests/Inputs/shtest-shell/Output/diff-unified.txt.tmp.foo 
# |            831: # .---command stderr------------ 
# | check:468'0                                     X error: no match found
# |            832: # | Traceback (most recent call last): 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            833: # | File "/home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/utils/lit/lit/builtin_commands/diff.py", line 275, in run 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            834: # | flags.num_context_lines = int(a) 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            835: # | ^^^^^^ 
# | check:468'0     ~~~~~~~~~~~
# |            836: # | ValueError: invalid literal for int() with base 10: '30.1' 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |              .
# |              .
# |              .
# |            842: # | main(sys.argv) 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~
# |            843: # | File "/home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/utils/lit/lit/builtin_commands/diff.py", line 323, in main 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            844: # | sys.exit(run(argv, sys.stdin.buffer, out, sys.stderr.buffer, os.getcwd())) 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            845: # | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            846: # | File "/home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/utils/lit/lit/builtin_commands/diff.py", line 279, in run 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            847: # | stderr.write("Error: invalid '-U' argument: {}\n".format(a)) 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | check:468'1                   ?                                                   possible intended match
# |            848: # | TypeError: a bytes-like object is required, not 'str' 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            849: # `----------------------------- 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            850: # error: command failed with exit status: 1 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            851: # executed command: true 
# | check:468'0     ~~~~~~~~~~~~~~~~~~~~~~~~~
# |            852: # RUN: at line 35 
# | check:468'0     ~~~~~~~~~~~~~~~~~~
# |              .
# |              .
# |              .
# | >>>>>>
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/204869