Allows for exclude as a multiline basic string in TOML files

Multiple regexes are expressed as a sequence.

Fixes python#11825.

docs/source/config_file.rst

@@ -214,6 +214,31 @@ section of the command line docs.
 
     This option may only be set in the global section (``[mypy]``).
 
+    .. note::
+
+       Note that the format TOML is slightly different. It can be either a single string
+       (including a multi-line string) -- which is treated as a single regular
+       expression -- or an array of such strings. The following TOML examples are
+       equivalent to the above INI file.
+
+       .. code-block:: toml
+
+         [tool.mypy]
+         exclude = [
+             "^file1\.py$",
+             "^file2\.py$",
+         ]
+
+       .. code-block:: toml
+
+         [tool.mypy]
+         exclude = """(?x)(
+             ^file1\.py$
+             |^file2\.py$",
+         )"""
+
+       See :ref:`using-a-pyproject-toml`.
+
 .. confval:: namespace_packages
 
     :type: boolean
@@ -907,6 +932,8 @@ These options may only be set in the global section (``[mypy]``).
     Controls how much debug output will be generated.  Higher numbers are more verbose.
 
 
+.. _using-a-pyproject-toml:
+
 Using a pyproject.toml file
 ***************************
 
@@ -965,6 +992,10 @@ of your repo (or append it to the end of an existing ``pyproject.toml`` file) an
     python_version = "2.7"
     warn_return_any = true
     warn_unused_configs = true
+    exclude = [
+        "^file1\.py$",
+        "^file2\.py$",
+    ]
 
     # mypy per-module options:
 

mypy/config_parser.py

@@ -57,6 +57,12 @@ def expand_path(path: str) -> str:
     return os.path.expandvars(os.path.expanduser(path))
 
 
+def str_or_seq_of_strs_as_list_of_strs(v: Union[str, Sequence[str]]) -> List[str]:
+    if isinstance(v, str):
+        return [v.strip()] if v.strip() else []
+    return [p.strip() for p in v if p.strip()]
+
+
 def split_and_match_files_list(paths: Sequence[str]) -> List[str]:
     """Take a list of files/directories (with support for globbing through the glob library).
 
@@ -143,6 +149,7 @@ def check_follow_imports(choice: str) -> str:
     'disable_error_code': try_split,
     'enable_error_code': try_split,
     'package_root': try_split,
+    'exclude': str_or_seq_of_strs_as_list_of_strs,
 })
 
 

test-data/unit/cmdline.pyproject.test

@@ -80,3 +80,33 @@ def g(a: int) -> int:
 [out]
 pyproject.toml: toml config file contains [[tool.mypy.overrides]] sections with conflicting values. Module 'x' has two different values for 'disallow_untyped_defs'
 == Return code: 0
+
+[case testMultilineExcludePyprojectTOML]
+# cmd: mypy x
+[file pyproject.toml]
+\[tool.mypy]
+exclude = """(?x)(
+    (^|/)[^/]*skipme_\\.py$
+    |(^|/)_skipme[^/]*\\.py$
+)"""
+[file x/__init__.py]
+i: int = 0
+[file x/_skipme_please.py]
+This isn't even syntatically valid!
+[file x/please_skipme_.py]
+Neither is this!
+
+[case testSequenceExcludePyprojectTOML]
+# cmd: mypy x
+[file pyproject.toml]
+\[tool.mypy]
+exclude = [
+    "(^|/)[^/]*skipme_\\.py$",
+    "(^|/)_skipme[^/]*\\.py$",
+]
+[file x/__init__.py]
+i: int = 0
+[file x/_skipme_please.py]
+This isn't even syntatically valid!
+[file x/please_skipme_.py]
+Neither is this!