Revert "Add fs.relative_to()"

This reverts commit f52bcaa27fc125ab9ae583af466ba99c164169f3.

It did not pass CI, and was merged anyway because there were two CI
errors in the same cygwin job. The other error was not the fault of this
commit, and since cygwin errors were glossed over because they were
"expected", the presence of a new error *added* by this commit was
overlooked.

Per the meson development policy, PRs which result in CI errors
can/should be reverted at will, no questions asked.

6 files changed, 8 insertions, 116 deletions

diff --git a/docs/markdown/Fs-module.md b/docs/markdown/Fs-module.md
index f136bb904..cc67355b5 100644
--- a/docs/markdown/Fs-module.md
+++ b/docs/markdown/Fs-module.md
@@ -224,20 +224,6 @@ fs.stem('foo/bar/baz.dll.a')  # baz.dll
    project. If the file specified by `path` is a `files()` object it
    cannot refer to a built file.
 
-### relative_to
-
-*Since 1.3.0*
-
-Return a relative filepath. In the event a relative path could not be found, the
-absolute path of `to` is returned. Relative path arguments will be assumed to be
-relative to `meson.current_source_dir()`.
-
-Has the following positional arguments:
-   - to `str | file | custom_tgt | custom_idx | tgt`: end path
-   - from `str | file | custom_tgt | custom_idx | tgt`: start path
-
-returns:
-   - a string
 
 ### copyfile
 
diff --git a/docs/markdown/snippets/fs_relative_to.md b/docs/markdown/snippets/fs_relative_to.md
deleted file mode 100644
index 82e6a4268..000000000
--- a/docs/markdown/snippets/fs_relative_to.md
+++ /dev/null
@@ -1,17 +0,0 @@
-## `fs.relative_to()`
-
-The `fs` module now has a `relative_to` method. The method will return the
-relative path from argument one to argument two, if one exists. Otherwise, the
-absolute path to argument one is returned.
-
-```meson
-assert(fs.relative_to('c:\\prefix\\lib', 'c:\\prefix\\bin') == '..\\lib')
-assert(fs.relative_to('c:\\proj1\\foo', 'd:\\proj1\\bar') == 'c:\\proj1\\foo')
-assert(fs.relative_to('prefix\\lib\\foo', 'prefix') == 'lib\\foo')
-
-assert(fs.relative_to('/prefix/lib', '/prefix/bin') == '../lib')
-assert(fs.relative_to('prefix/lib/foo', 'prefix') == 'lib/foo')
-```
-
-In addition to strings, it can handle files, custom targets, custom target
-indices, and build targets.
diff --git a/mesonbuild/modules/fs.py b/mesonbuild/modules/fs.py
index 89aead06b..53174d231 100644
--- a/mesonbuild/modules/fs.py
+++ b/mesonbuild/modules/fs.py
@@ -20,16 +20,19 @@ import typing as T
 
 from . import ExtensionModule, ModuleReturnValue, ModuleInfo
 from .. import mlog
-from ..build import BuildTarget, CustomTarget, CustomTargetIndex, InvalidArguments
+from ..build import CustomTarget, InvalidArguments
 from ..interpreter.type_checking import INSTALL_KW, INSTALL_MODE_KW, INSTALL_TAG_KW, NoneType
 from ..interpreterbase import FeatureNew, KwargInfo, typed_kwargs, typed_pos_args, noKwargs
-from ..mesonlib import File, MesonException, has_path_sep, path_is_in_root, relpath
+from ..mesonlib import (
+    File,
+    MesonException,
+    has_path_sep,
+    path_is_in_root,
+)
 
 if T.TYPE_CHECKING:
     from . import ModuleState
-    from ..build import BuildTargetTypes
     from ..interpreter import Interpreter
-    from ..interpreterbase import TYPE_kwargs
     from ..mesonlib import FileOrString, FileMode
 
     from typing_extensions import TypedDict
@@ -72,7 +75,6 @@ class FSModule(ExtensionModule):
             'stem': self.stem,
             'read': self.read,
             'copyfile': self.copyfile,
-            'relative_to': self.relative_to,
         })
 
     def _absolute_dir(self, state: 'ModuleState', arg: 'FileOrString') -> Path:
@@ -310,23 +312,6 @@ class FSModule(ExtensionModule):
 
         return ModuleReturnValue(ct, [ct])
 
-    @FeatureNew('fs.relative_to', '1.3.0')
-    @typed_pos_args('fs.relative_to', (str, File, CustomTarget, CustomTargetIndex, BuildTarget), (str, File, CustomTarget, CustomTargetIndex, BuildTarget))
-    @noKwargs
-    def relative_to(self, state: ModuleState, args: T.Tuple[T.Union[FileOrString, BuildTargetTypes], T.Union[FileOrString, BuildTargetTypes]], kwargs: TYPE_kwargs) -> str:
-        def to_path(arg: T.Union[FileOrString, CustomTarget, CustomTargetIndex, BuildTarget]) -> str:
-            if isinstance(arg, File):
-                return arg.absolute_path(state.environment.source_dir, state.environment.build_dir)
-            elif isinstance(arg, (CustomTarget, CustomTargetIndex, BuildTarget)):
-                return state.backend.get_target_filename_abs(arg)
-            else:
-                return os.path.join(state.environment.source_dir, state.subdir, arg)
-
-        t = to_path(args[0])
-        f = to_path(args[1])
-
-        return relpath(t, f)
-
 
 def initialize(*args: T.Any, **kwargs: T.Any) -> FSModule:
     return FSModule(*args, **kwargs)
diff --git a/test cases/common/220 fs module/meson.build b/test cases/common/220 fs module/meson.build
index 7f113d66e..b860fc8a3 100644
--- a/test cases/common/220 fs module/meson.build
+++ b/test cases/common/220 fs module/meson.build
@@ -1,4 +1,4 @@
-project('fs module test', 'c')
+project('fs module test')
 
 is_windows = build_machine.system() == 'windows'
 
@@ -139,29 +139,6 @@ assert(fs.name('foo/bar/baz.dll.a') == 'baz.dll.a', 'failed to get basename with
 assert(fs.stem('foo/bar/baz.dll') == 'baz', 'failed to get stem with suffix')
 assert(fs.stem('foo/bar/baz.dll.a') == 'baz.dll', 'failed to get stem with compound suffix')
 
-# relative_to
-if build_machine.system() == 'windows'
-  # strings
-  assert(fs.relative_to('c:\\prefix\\lib\\foo', 'c:\\prefix') == 'lib\\foo')
-  assert(fs.relative_to('c:\\prefix\\lib', 'c:\\prefix\\bin') == '..\\lib')
-  assert(fs.relative_to('c:\\proj1\\foo', 'd:\\proj1\\bar') == 'c:\\proj1\\foo')
-  assert(fs.relative_to('prefix\\lib\\foo', 'prefix') == 'lib\\foo')
-  assert(fs.relative_to('prefix\\lib', 'prefix\\bin') == '..\\lib')
-  assert(fs.relative_to('proj1\\foo', 'proj1\\bar') == '..\\foo')
-  assert(fs.relative_to('subdir/subdirfile.txt', meson.current_source_dir()) == 'subdir\\subdirfile.txt')
-  assert(fs.relative_to(files('meson.build'), files('subdir/meson.build')) == '..\\..\\meson.build')
-  assert(fs.relative_to(files('meson.build'), 'subdir/meson.build') == '..\\..\\meson.build')
-else
-  # strings
-  assert(fs.relative_to('/prefix/lib/foo', '/prefix') == 'lib/foo')
-  assert(fs.relative_to('/prefix/lib', '/prefix/bin') == '../lib')
-  assert(fs.relative_to('prefix/lib/foo', 'prefix') == 'lib/foo')
-  assert(fs.relative_to('prefix/lib', 'prefix/bin') == '../lib')
-  assert(fs.relative_to('subdir/subdirfile.txt', meson.current_source_dir()) == 'subdir/subdirfile.txt')
-  assert(fs.relative_to(files('meson.build'), files('subdir/meson.build')) == '../../meson.build')
-  assert(fs.relative_to(files('meson.build'), 'subdir/meson.build') == '../../meson.build')
-endif
-
 subdir('subdir')
 
 subproject('subbie')
diff --git a/test cases/common/220 fs module/subdir/btgt.c b/test cases/common/220 fs module/subdir/btgt.c
deleted file mode 100644
index 8479e67d1..000000000
--- a/test cases/common/220 fs module/subdir/btgt.c
+++ /dev/null
@@ -1,5 +0,0 @@
-int
-main(void)
-{
-    return 0;
-}
diff --git a/test cases/common/220 fs module/subdir/meson.build b/test cases/common/220 fs module/subdir/meson.build
index a0f3091fa..0cd2475e9 100644
--- a/test cases/common/220 fs module/subdir/meson.build
+++ b/test cases/common/220 fs module/subdir/meson.build
@@ -4,37 +4,3 @@ assert(fs.is_samepath(meson.project_source_root(), '..'), 'is_samepath not detec
 assert(fs.is_samepath(meson.project_build_root(), meson.current_build_dir() / '..'), 'is_samepath not detecting same directory')
 
 assert(fs.is_samepath(subdirfiles[0], 'subdirfile.txt'), 'is_samepath not detecting same directory when using File and str')
-
-# More relative_to to test subdir/builddir components
-
-build_to_src = fs.relative_to(meson.current_source_dir(), meson.current_build_dir())
-src_to_build = fs.relative_to(meson.current_build_dir(), meson.current_source_dir())
-
-btgt = executable('btgt', 'btgt.c')
-ctgt = fs.copyfile('subdirfile.txt')
-
-if build_machine.system() == 'windows'
-  # Test that CustomTarget works
-  assert(fs.relative_to('subdirfile.txt', ctgt) == '..\\@0@\\subdirfile.txt'.format(build_to_src))
-  assert(fs.relative_to(ctgt, 'subdirfile.txt') == '..\\@0@\\subdirfile.txt'.format(src_to_build))
-  # Test that CustomTargetIndex works
-  assert(fs.relative_to('subdirfile.txt', ctgt[0]) == '..\\@0@\\subdirfile.txt'.format(build_to_src))
-  assert(fs.relative_to(ctgt[0], 'subdirfile.txt') == '..\\@0@\\subdirfile.txt'.format(src_to_build))
-  # Test that BuildTarget works
-  assert(fs.relative_to('subdirfile.txt', btgt) == '..\\@0@\\subdirfile.txt'.format(build_to_src))
-  assert(fs.relative_to(btgt, 'subdirfile.txt') == '..\\@0@\\btgt.exe'.format(src_to_build))
-else
-  # Test that CustomTarget works
-  assert(fs.relative_to('subdirfile.txt', ctgt) == '../@0@/subdirfile.txt'.format(build_to_src))
-  assert(fs.relative_to(ctgt, 'subdirfile.txt') == '../@0@/subdirfile.txt'.format(src_to_build))
-  # Test that CustomTargetIndex works
-  assert(fs.relative_to('subdirfile.txt', ctgt[0]) == '../@0@/subdirfile.txt'.format(build_to_src))
-  assert(fs.relative_to(ctgt[0], 'subdirfile.txt') == '../@0@/subdirfile.txt'.format(src_to_build))
-  # Test that BuildTarget works
-  assert(fs.relative_to('subdirfile.txt', btgt) == '../@0@/subdirfile.txt'.format(build_to_src))
-  if host_machine.system() == 'windows'
-    assert(fs.relative_to(btgt, 'subdirfile.txt') == '../@0@/btgt.exe'.format(src_to_build))
-  else
-    assert(fs.relative_to(btgt, 'subdirfile.txt') == '../@0@/btgt'.format(src_to_build))
-  endif
-endif