Success message missing when reveal_type() used.

[mrolle45]

Bug Report

I have something like if TYPE_CHECKING: reveal_type(foo) in a module (in 5 places).
mypy finds no errors, but the line that says "success" is missing.

Here's two sets of output from mypy, first with reveal_type() in the module, and second without.

D:\Solutions\trunk\Python\Sass>mypy .
solver\common.py:299: note: Revealed type is "Any"
solver\common.py:366: note: Revealed type is "Any"
solver\common.py:521: note: Revealed type is "solver.instruct.InstrTab"
solver\common.py:522: note: Revealed type is "Any"
solver\common.py:523: note: Revealed type is "Any"

D:\Solutions\trunk\Python\Sass>mypy .
Success: no issues found in 52 source files

What I think is correct output, in the first case, is

D:\Solutions\trunk\Python\Sass>mypy .
solver\common.py:299: note: Revealed type is "Any"
solver\common.py:366: note: Revealed type is "Any"
solver\common.py:521: note: Revealed type is "solver.instruct.InstrTab"
solver\common.py:522: note: Revealed type is "Any"
solver\common.py:523: note: Revealed type is "Any"
Success: no issues found in 52 source files

Your Environment

• Mypy version used: 0,92`
• Python version used: 3.7
• Operating system and version: Windows 10

[KotlinIsland]

This happens if there are only notes (notes still cause failure, but no error count) in the output:
playground https://mypy-play.net/?mypy=latest&python=3.10&gist=3d64dc19218346533773b8f84b9535fa

[mrolle45]

I think that if there are only notes, and no errors or blockers, the return code should be success as well.

I wrote a replacement for the code in main() lines 116-131 that produces the desired return status and error summary:

    code = 0
    if messages:
        n_errors, n_files = util.count_stats(messages)
        code = 1
    if blockers: code = 2
    if options.error_summary:
        if messages and n_errors:
            summary = formatter.format_error(
                n_errors, n_files, len(sources), blockers=blockers,
                use_color=options.color_output
            )
            stdout.write(summary + '\n')
        if code == 0:
            stdout.write(formatter.format_success(len(sources), options.color_output) + '\n')
        stdout.flush()

You can use this code.

[KotlinIsland]

@97littleleaf11 Here is a workaround:

from typing import *

error: Literal[": error:"]
reveal_type(error)

> mypy main.py
main.py:4: note: Revealed type is "Literal[': error:']"
Found 1 error in 1 file (checked 1 source file)

https://mypy-play.net/?mypy=latest&python=3.10&gist=50bd436765ad217d1cc28568221c7c5f

[97littleleaf11]

@KotlinIsland I think we can leave this corner case behind.

[KotlinIsland]

What I meant was, it is a workaround to the issue in the OP 😂