environment: move tool detection functions to a new module

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

17 files changed, 292 insertions, 272 deletions

diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 769de93ec..0196e84d2 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -20,10 +20,11 @@ import typing as T
 
 from . import backends
 from .. import modules
-from .. import environment, mesonlib
+from .. import mesonlib
 from .. import build
 from .. import mlog
 from .. import compilers
+from .. import tooldetect
 from ..arglist import CompilerArgs
 from ..compilers import Compiler, is_library
 from ..linkers import ArLikeLinker, RSPFileSyntax
@@ -595,7 +596,7 @@ class NinjaBackend(backends.Backend):
                     mlog.debug('cuda enabled globally, disabling thin archives for {}, since nvcc/nvlink cannot handle thin archives natively'.format(for_machine))
                     self.allow_thin_archives[for_machine] = False
 
-        ninja = environment.detect_ninja_command_and_version(log=True)
+        ninja = tooldetect.detect_ninja_command_and_version(log=True)
         if self.environment.coredata.optstore.get_value_for(OptionKey('vsenv')):
             builddir = Path(self.environment.get_build_dir())
             try:
@@ -656,7 +657,7 @@ class NinjaBackend(backends.Backend):
             key = OptionKey('b_coverage')
             if key in self.environment.coredata.optstore and\
                     self.environment.coredata.optstore.get_value_for('b_coverage'):
-                gcovr_exe, gcovr_version, lcov_exe, lcov_version, genhtml_exe, llvm_cov_exe = environment.find_coverage_tools(self.environment.coredata)
+                gcovr_exe, gcovr_version, lcov_exe, lcov_version, genhtml_exe, llvm_cov_exe = tooldetect.find_coverage_tools(self.environment.coredata)
                 mlog.debug(f'Using {gcovr_exe} ({gcovr_version}), {lcov_exe} and {llvm_cov_exe} for code coverage')
                 if gcovr_exe or (lcov_exe and genhtml_exe):
                     self.add_build_comment(NinjaComment('Coverage rules'))
@@ -3875,7 +3876,7 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
         self.add_build(elem)
 
     def generate_scanbuild(self) -> None:
-        if not environment.detect_scanbuild():
+        if not tooldetect.detect_scanbuild():
             return
         if 'scan-build' in self.all_outputs:
             return
@@ -3916,16 +3917,16 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
         self.add_build(elem)
 
     def generate_clangformat(self) -> None:
-        if not environment.detect_clangformat():
+        if not tooldetect.detect_clangformat():
             return
         self.generate_clangtool('format')
         self.generate_clangtool('format', 'check')
 
     def generate_clangtidy(self) -> None:
-        if not environment.detect_clangtidy():
+        if not tooldetect.detect_clangtidy():
             return
         self.generate_clangtool('tidy', need_pch=True)
-        if not environment.detect_clangapply():
+        if not tooldetect.detect_clangapply():
             return
         self.generate_clangtool('tidy', 'fix', need_pch=True)
 
diff --git a/mesonbuild/dependencies/dev.py b/mesonbuild/dependencies/dev.py
index d9f8fb1ee..aa7c4686b 100644
--- a/mesonbuild/dependencies/dev.py
+++ b/mesonbuild/dependencies/dev.py
@@ -15,7 +15,7 @@ import functools
 from mesonbuild.interpreterbase.decorators import FeatureDeprecated
 
 from .. import mesonlib, mlog
-from ..environment import get_llvm_tool_names
+from ..tooldetect import get_llvm_tool_names
 from ..mesonlib import version_compare, version_compare_many, search_version
 from .base import DependencyException, DependencyMethods, detect_compiler, strip_system_includedirs, strip_system_libdirs, SystemDependency, ExternalDependency, DependencyTypeName
 from .cmake import CMakeDependency
diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index 4d89c88ef..90b10697a 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -5,7 +5,7 @@
 from __future__ import annotations
 
 import itertools
-import os, re, shutil
+import os, re
 import typing as T
 import collections
 
@@ -17,8 +17,8 @@ from . import options
 
 from .mesonlib import (
     MesonException, MachineChoice, Popen_safe, PerMachine,
-    PerMachineDefaultable, PerThreeMachineDefaultable, split_args, quote_arg,
-    search_version, MesonBugException
+    PerMachineDefaultable, PerThreeMachineDefaultable, split_args,
+    MesonBugException
 )
 from .options import OptionKey
 from . import mlog
@@ -78,239 +78,6 @@ def _get_env_var(for_machine: MachineChoice, is_cross: bool, var_name: str) -> T
     return value
 
 
-def detect_gcovr(gcovr_exe: str = 'gcovr', min_version: str = '3.3', log: bool = False) \
-        -> T.Union[T.Tuple[None, None], T.Tuple[str, str]]:
-    try:
-        p, found = Popen_safe([gcovr_exe, '--version'])[0:2]
-    except (FileNotFoundError, PermissionError):
-        # Doesn't exist in PATH or isn't executable
-        return None, None
-    found = search_version(found)
-    if p.returncode == 0 and mesonlib.version_compare(found, '>=' + min_version):
-        if log:
-            mlog.log('Found gcovr-{} at {}'.format(found, quote_arg(shutil.which(gcovr_exe))))
-        return gcovr_exe, found
-    return None, None
-
-def detect_lcov(lcov_exe: str = 'lcov', log: bool = False) \
-        -> T.Union[T.Tuple[None, None], T.Tuple[str, str]]:
-    try:
-        p, found = Popen_safe([lcov_exe, '--version'])[0:2]
-    except (FileNotFoundError, PermissionError):
-        # Doesn't exist in PATH or isn't executable
-        return None, None
-    found = search_version(found)
-    if p.returncode == 0 and found:
-        if log:
-            mlog.log('Found lcov-{} at {}'.format(found, quote_arg(shutil.which(lcov_exe))))
-        return lcov_exe, found
-    return None, None
-
-def detect_llvm_cov(suffix: T.Optional[str] = None) -> T.Optional[str]:
-    # If there's a known suffix or forced lack of suffix, use that
-    if suffix is not None:
-        if suffix == '':
-            tool = 'llvm-cov'
-        else:
-            tool = f'llvm-cov-{suffix}'
-        if shutil.which(tool) is not None:
-            return tool
-    else:
-        # Otherwise guess in the dark
-        tools = get_llvm_tool_names('llvm-cov')
-        for tool in tools:
-            if shutil.which(tool):
-                return tool
-    return None
-
-def compute_llvm_suffix(coredata: coredata.CoreData) -> T.Optional[str]:
-    # Check to see if the user is trying to do coverage for either a C or C++ project
-    compilers = coredata.compilers[MachineChoice.BUILD]
-    cpp_compiler_is_clang = 'cpp' in compilers and compilers['cpp'].id == 'clang'
-    c_compiler_is_clang = 'c' in compilers and compilers['c'].id == 'clang'
-    # Extract first the C++ compiler if available. If it's a Clang of some kind, compute the suffix if possible
-    if cpp_compiler_is_clang:
-        suffix = compilers['cpp'].version.split('.')[0]
-        return suffix
-
-    # Then the C compiler, again checking if it's some kind of Clang and computing the suffix
-    if c_compiler_is_clang:
-        suffix = compilers['c'].version.split('.')[0]
-        return suffix
-
-    # Neither compiler is a Clang, or no compilers are for C or C++
-    return None
-
-def detect_lcov_genhtml(lcov_exe: str = 'lcov', genhtml_exe: str = 'genhtml') \
-        -> T.Tuple[str, T.Optional[str], str]:
-    lcov_exe, lcov_version = detect_lcov(lcov_exe)
-    if shutil.which(genhtml_exe) is None:
-        genhtml_exe = None
-
-    return lcov_exe, lcov_version, genhtml_exe
-
-def find_coverage_tools(coredata: coredata.CoreData) -> T.Tuple[T.Optional[str], T.Optional[str], T.Optional[str], T.Optional[str], T.Optional[str], T.Optional[str]]:
-    gcovr_exe, gcovr_version = detect_gcovr()
-
-    llvm_cov_exe = detect_llvm_cov(compute_llvm_suffix(coredata))
-    # Some platforms may provide versioned clang but only non-versioned llvm utils
-    if llvm_cov_exe is None:
-        llvm_cov_exe = detect_llvm_cov('')
-
-    lcov_exe, lcov_version, genhtml_exe = detect_lcov_genhtml()
-
-    return gcovr_exe, gcovr_version, lcov_exe, lcov_version, genhtml_exe, llvm_cov_exe
-
-def detect_ninja(version: str = '1.8.2', log: bool = False) -> T.Optional[T.List[str]]:
-    r = detect_ninja_command_and_version(version, log)
-    return r[0] if r else None
-
-def detect_ninja_command_and_version(version: str = '1.8.2', log: bool = False) -> T.Optional[T.Tuple[T.List[str], str]]:
-    env_ninja = os.environ.get('NINJA', None)
-    for n in [env_ninja] if env_ninja else ['ninja', 'ninja-build', 'samu']:
-        prog = ExternalProgram(n, silent=True)
-        if not prog.found():
-            continue
-        try:
-            p, found = Popen_safe(prog.command + ['--version'])[0:2]
-        except (FileNotFoundError, PermissionError):
-            # Doesn't exist in PATH or isn't executable
-            continue
-        found = found.strip()
-        # Perhaps we should add a way for the caller to know the failure mode
-        # (not found or too old)
-        if p.returncode == 0 and mesonlib.version_compare(found, '>=' + version):
-            if log:
-                name = os.path.basename(n)
-                if name.endswith('-' + found):
-                    name = name[0:-1 - len(found)]
-                if name == 'ninja-build':
-                    name = 'ninja'
-                if name == 'samu':
-                    name = 'samurai'
-                mlog.log('Found {}-{} at {}'.format(name, found,
-                         ' '.join([quote_arg(x) for x in prog.command])))
-            return (prog.command, found)
-    return None
-
-def get_llvm_tool_names(tool: str) -> T.List[str]:
-    # Ordered list of possible suffixes of LLVM executables to try. Start with
-    # base, then try newest back to oldest (3.5 is arbitrary), and finally the
-    # devel version. Please note that the development snapshot in Debian does
-    # not have a distinct name. Do not move it to the beginning of the list
-    # unless it becomes a stable release.
-    suffixes = [
-        '', # base (no suffix)
-        '-21.1', '21.1',
-        '-21',  '21',
-        '-20.1', '20.1',
-        '-20',  '20',
-        '-19.1', '19.1',
-        '-19',  '19',
-        '-18.1', '18.1',
-        '-18',  '18',
-        '-17',  '17',
-        '-16',  '16',
-        '-15',  '15',
-        '-14',  '14',
-        '-13',  '13',
-        '-12',  '12',
-        '-11',  '11',
-        '-10',  '10',
-        '-9',   '90',
-        '-8',   '80',
-        '-7',   '70',
-        '-6.0', '60',
-        '-5.0', '50',
-        '-4.0', '40',
-        '-3.9', '39',
-        '-3.8', '38',
-        '-3.7', '37',
-        '-3.6', '36',
-        '-3.5', '35',
-        '-20',    # Debian development snapshot
-        '-devel', # FreeBSD development snapshot
-    ]
-    names: T.List[str] = []
-    for suffix in suffixes:
-        names.append(tool + suffix)
-    return names
-
-def detect_scanbuild() -> T.List[str]:
-    """ Look for scan-build binary on build platform
-
-    First, if a SCANBUILD env variable has been provided, give it precedence
-    on all platforms.
-
-    For most platforms, scan-build is found is the PATH contains a binary
-    named "scan-build". However, some distribution's package manager (FreeBSD)
-    don't. For those, loop through a list of candidates to see if one is
-    available.
-
-    Return: a single-element list of the found scan-build binary ready to be
-        passed to Popen()
-    """
-    exelist: T.List[str] = []
-    if 'SCANBUILD' in os.environ:
-        exelist = split_args(os.environ['SCANBUILD'])
-
-    else:
-        tools = get_llvm_tool_names('scan-build')
-        for tool in tools:
-            which = shutil.which(tool)
-            if which is not None:
-                exelist = [which]
-                break
-
-    if exelist:
-        tool = exelist[0]
-        if os.path.isfile(tool) and os.access(tool, os.X_OK):
-            return [tool]
-    return []
-
-def detect_clangformat() -> T.List[str]:
-    """ Look for clang-format binary on build platform
-
-    Do the same thing as detect_scanbuild to find clang-format except it
-    currently does not check the environment variable.
-
-    Return: a single-element list of the found clang-format binary ready to be
-        passed to Popen()
-    """
-    tools = get_llvm_tool_names('clang-format')
-    for tool in tools:
-        path = shutil.which(tool)
-        if path is not None:
-            return [path]
-    return []
-
-def detect_clangtidy() -> T.List[str]:
-    """ Look for clang-tidy binary on build platform
-
-    Return: a single-element list of the found clang-tidy binary ready to be
-        passed to Popen()
-    """
-    tools = get_llvm_tool_names('clang-tidy')
-    for tool in tools:
-        path = shutil.which(tool)
-        if path is not None:
-            return [path]
-    return []
-
-def detect_clangapply() -> T.List[str]:
-    """ Look for clang-apply-replacements binary on build platform
-
-    Return: a single-element list of the found clang-apply-replacements binary
-        ready to be passed to Popen()
-    """
-    tools = get_llvm_tool_names('clang-apply-replacements')
-    for tool in tools:
-        path = shutil.which(tool)
-        if path is not None:
-            return [path]
-    return []
-
-
 class Environment:
     private_dir = 'meson-private'
     log_dir = 'meson-logs'
diff --git a/mesonbuild/mcompile.py b/mesonbuild/mcompile.py
index cfaeb7960..72219588c 100644
--- a/mesonbuild/mcompile.py
+++ b/mesonbuild/mcompile.py
@@ -18,7 +18,7 @@ from . import mlog
 from . import mesonlib
 from .options import OptionKey
 from .mesonlib import MesonException, RealPathAction, join_args, listify_array_value, setup_vsenv
-from mesonbuild.environment import detect_ninja
+from mesonbuild.tooldetect import detect_ninja
 from mesonbuild import build
 
 if T.TYPE_CHECKING:
diff --git a/mesonbuild/mdist.py b/mesonbuild/mdist.py
index a68736406..5d9967420 100644
--- a/mesonbuild/mdist.py
+++ b/mesonbuild/mdist.py
@@ -20,7 +20,8 @@ import typing as T
 from dataclasses import dataclass
 from glob import glob
 from pathlib import Path
-from mesonbuild.environment import Environment, detect_ninja
+from mesonbuild.environment import Environment
+from mesonbuild.tooldetect import detect_ninja
 from mesonbuild.mesonlib import (GIT, MesonException, RealPathAction, get_meson_command, quiet_git,
                                  windows_proof_rmtree, setup_vsenv)
 from .options import OptionKey
diff --git a/mesonbuild/minit.py b/mesonbuild/minit.py
index 192c75a68..7d0d051ad 100644
--- a/mesonbuild/minit.py
+++ b/mesonbuild/minit.py
@@ -17,7 +17,7 @@ import typing as T
 
 from mesonbuild import build, mesonlib, mlog
 from mesonbuild.coredata import FORBIDDEN_TARGET_NAMES
-from mesonbuild.environment import detect_ninja
+from mesonbuild.tooldetect import detect_ninja
 from mesonbuild.templates.mesontemplates import create_meson_build
 from mesonbuild.templates.samplefactory import sample_generator
 from mesonbuild.options import OptionKey
diff --git a/mesonbuild/minstall.py b/mesonbuild/minstall.py
index eec22be67..f9c848042 100644
--- a/mesonbuild/minstall.py
+++ b/mesonbuild/minstall.py
@@ -15,7 +15,7 @@ import sys
 import typing as T
 import re
 
-from . import build, environment
+from . import build, tooldetect
 from .backend.backends import InstallData
 from .mesonlib import (MesonException, Popen_safe, RealPathAction, is_windows,
                        is_aix, setup_vsenv, pickle_load, is_osx)
@@ -803,7 +803,7 @@ def rebuild_all(wd: str, backend: str) -> bool:
         print('Only ninja backend is supported to rebuild the project before installation.')
         return True
 
-    ninja = environment.detect_ninja()
+    ninja = tooldetect.detect_ninja()
     if not ninja:
         print("Can't find ninja, can't rebuild test.")
         return False
diff --git a/mesonbuild/mtest.py b/mesonbuild/mtest.py
index cdba8a60e..f5e4bb519 100644
--- a/mesonbuild/mtest.py
+++ b/mesonbuild/mtest.py
@@ -29,7 +29,7 @@ import unicodedata
 import xml.etree.ElementTree as et
 
 from . import build
-from . import environment
+from . import tooldetect
 from . import mlog
 from .coredata import MesonVersionMismatchException, major_versions_differ
 from .coredata import version as coredata_version
@@ -1702,7 +1702,7 @@ class TestHarness:
         if self.options.no_rebuild:
             return
 
-        self.ninja = environment.detect_ninja()
+        self.ninja = tooldetect.detect_ninja()
         if not self.ninja:
             print("Can't find ninja, can't rebuild test.")
             # If ninja can't be found return exit code 127, indicating command
diff --git a/mesonbuild/scripts/clangformat.py b/mesonbuild/scripts/clangformat.py
index a3c19e9ad..281cb10ca 100644
--- a/mesonbuild/scripts/clangformat.py
+++ b/mesonbuild/scripts/clangformat.py
@@ -8,7 +8,7 @@ from pathlib import Path
 import sys
 
 from .run_tool import run_clang_tool, run_with_buffered_output
-from ..environment import detect_clangformat
+from ..tooldetect import detect_clangformat
 from ..mesonlib import version_compare
 from ..programs import ExternalProgram
 import typing as T
diff --git a/mesonbuild/scripts/clangtidy.py b/mesonbuild/scripts/clangtidy.py
index e5f702491..da4d45474 100644
--- a/mesonbuild/scripts/clangtidy.py
+++ b/mesonbuild/scripts/clangtidy.py
@@ -12,7 +12,7 @@ import shutil
 import sys
 
 from .run_tool import run_with_buffered_output, run_clang_tool_on_sources
-from ..environment import detect_clangtidy, detect_clangapply
+from ..tooldetect import detect_clangtidy, detect_clangapply
 import typing as T
 
 async def run_clang_tidy(fname: Path, tidyexe: list, builddir: Path, fixesdir: T.Optional[Path]) -> int:
diff --git a/mesonbuild/scripts/coverage.py b/mesonbuild/scripts/coverage.py
index a4dfebfb9..f51536358 100644
--- a/mesonbuild/scripts/coverage.py
+++ b/mesonbuild/scripts/coverage.py
@@ -3,7 +3,7 @@
 
 from __future__ import annotations
 
-from mesonbuild import environment, mesonlib
+from mesonbuild import tooldetect, mesonlib
 
 import argparse, re, sys, os, subprocess, pathlib, stat, shutil
 import typing as T
@@ -16,11 +16,11 @@ def coverage(outputs: T.List[str], source_root: str, subproject_root: str, build
     if gcovr_exe == '':
         gcovr_exe = None
     else:
-        gcovr_exe, gcovr_version = environment.detect_gcovr(gcovr_exe)
+        gcovr_exe, gcovr_version = tooldetect.detect_gcovr(gcovr_exe)
     if llvm_cov_exe == '' or shutil.which(llvm_cov_exe) is None:
         llvm_cov_exe = None
 
-    lcov_exe, lcov_version, genhtml_exe = environment.detect_lcov_genhtml()
+    lcov_exe, lcov_version, genhtml_exe = tooldetect.detect_lcov_genhtml()
 
     # load config files for tools if available in the source tree
     # - lcov requires manually specifying a per-project config
diff --git a/mesonbuild/scripts/scanbuild.py b/mesonbuild/scripts/scanbuild.py
index 20ce0a621..3bf791833 100644
--- a/mesonbuild/scripts/scanbuild.py
+++ b/mesonbuild/scripts/scanbuild.py
@@ -7,7 +7,7 @@ import subprocess
 import shutil
 import tempfile
 from ..cmdline import get_cmd_line_file, CmdLineFileParser
-from ..environment import detect_ninja, detect_scanbuild
+from ..tooldetect import detect_ninja, detect_scanbuild
 from ..mesonlib import windows_proof_rmtree, determine_worker_count
 from pathlib import Path
 import typing as T
diff --git a/mesonbuild/tooldetect.py b/mesonbuild/tooldetect.py
new file mode 100644
index 000000000..198a6ee33
--- /dev/null
+++ b/mesonbuild/tooldetect.py
@@ -0,0 +1,248 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright 2012-2020 The Meson development team
+# Copyright © 2023-2025 Intel Corporation
+
+from __future__ import annotations
+
+import os
+import shutil
+import typing as T
+
+from . import coredata
+from . import mesonlib
+from . import mlog
+from .mesonlib import MachineChoice, Popen_safe, search_version, quote_arg, split_args
+from .programs import ExternalProgram
+
+
+def detect_gcovr(gcovr_exe: str = 'gcovr', min_version: str = '3.3', log: bool = False) \
+        -> T.Union[T.Tuple[None, None], T.Tuple[str, str]]:
+    try:
+        p, found = Popen_safe([gcovr_exe, '--version'])[0:2]
+    except (FileNotFoundError, PermissionError):
+        # Doesn't exist in PATH or isn't executable
+        return None, None
+    found = search_version(found)
+    if p.returncode == 0 and mesonlib.version_compare(found, '>=' + min_version):
+        if log:
+            mlog.log('Found gcovr-{} at {}'.format(found, quote_arg(shutil.which(gcovr_exe))))
+        return gcovr_exe, found
+    return None, None
+
+def detect_lcov(lcov_exe: str = 'lcov', log: bool = False) \
+        -> T.Union[T.Tuple[None, None], T.Tuple[str, str]]:
+    try:
+        p, found = Popen_safe([lcov_exe, '--version'])[0:2]
+    except (FileNotFoundError, PermissionError):
+        # Doesn't exist in PATH or isn't executable
+        return None, None
+    found = search_version(found)
+    if p.returncode == 0 and found:
+        if log:
+            mlog.log('Found lcov-{} at {}'.format(found, quote_arg(shutil.which(lcov_exe))))
+        return lcov_exe, found
+    return None, None
+
+def detect_llvm_cov(suffix: T.Optional[str] = None) -> T.Optional[str]:
+    # If there's a known suffix or forced lack of suffix, use that
+    if suffix is not None:
+        if suffix == '':
+            tool = 'llvm-cov'
+        else:
+            tool = f'llvm-cov-{suffix}'
+        if shutil.which(tool) is not None:
+            return tool
+    else:
+        # Otherwise guess in the dark
+        tools = get_llvm_tool_names('llvm-cov')
+        for tool in tools:
+            if shutil.which(tool):
+                return tool
+    return None
+
+def compute_llvm_suffix(coredata: coredata.CoreData) -> T.Optional[str]:
+    # Check to see if the user is trying to do coverage for either a C or C++ project
+    compilers = coredata.compilers[MachineChoice.BUILD]
+    cpp_compiler_is_clang = 'cpp' in compilers and compilers['cpp'].id == 'clang'
+    c_compiler_is_clang = 'c' in compilers and compilers['c'].id == 'clang'
+    # Extract first the C++ compiler if available. If it's a Clang of some kind, compute the suffix if possible
+    if cpp_compiler_is_clang:
+        suffix = compilers['cpp'].version.split('.')[0]
+        return suffix
+
+    # Then the C compiler, again checking if it's some kind of Clang and computing the suffix
+    if c_compiler_is_clang:
+        suffix = compilers['c'].version.split('.')[0]
+        return suffix
+
+    # Neither compiler is a Clang, or no compilers are for C or C++
+    return None
+
+def detect_lcov_genhtml(lcov_exe: str = 'lcov', genhtml_exe: str = 'genhtml') \
+        -> T.Tuple[str, T.Optional[str], str]:
+    lcov_exe, lcov_version = detect_lcov(lcov_exe)
+    if shutil.which(genhtml_exe) is None:
+        genhtml_exe = None
+
+    return lcov_exe, lcov_version, genhtml_exe
+
+def find_coverage_tools(coredata: coredata.CoreData) -> T.Tuple[T.Optional[str], T.Optional[str], T.Optional[str], T.Optional[str], T.Optional[str], T.Optional[str]]:
+    gcovr_exe, gcovr_version = detect_gcovr()
+
+    llvm_cov_exe = detect_llvm_cov(compute_llvm_suffix(coredata))
+    # Some platforms may provide versioned clang but only non-versioned llvm utils
+    if llvm_cov_exe is None:
+        llvm_cov_exe = detect_llvm_cov('')
+
+    lcov_exe, lcov_version, genhtml_exe = detect_lcov_genhtml()
+
+    return gcovr_exe, gcovr_version, lcov_exe, lcov_version, genhtml_exe, llvm_cov_exe
+
+def detect_ninja(version: str = '1.8.2', log: bool = False) -> T.Optional[T.List[str]]:
+    r = detect_ninja_command_and_version(version, log)
+    return r[0] if r else None
+
+def detect_ninja_command_and_version(version: str = '1.8.2', log: bool = False) -> T.Optional[T.Tuple[T.List[str], str]]:
+    env_ninja = os.environ.get('NINJA', None)
+    for n in [env_ninja] if env_ninja else ['ninja', 'ninja-build', 'samu']:
+        prog = ExternalProgram(n, silent=True)
+        if not prog.found():
+            continue
+        try:
+            p, found = Popen_safe(prog.command + ['--version'])[0:2]
+        except (FileNotFoundError, PermissionError):
+            # Doesn't exist in PATH or isn't executable
+            continue
+        found = found.strip()
+        # Perhaps we should add a way for the caller to know the failure mode
+        # (not found or too old)
+        if p.returncode == 0 and mesonlib.version_compare(found, '>=' + version):
+            if log:
+                name = os.path.basename(n)
+                if name.endswith('-' + found):
+                    name = name[0:-1 - len(found)]
+                if name == 'ninja-build':
+                    name = 'ninja'
+                if name == 'samu':
+                    name = 'samurai'
+                mlog.log('Found {}-{} at {}'.format(name, found,
+                         ' '.join([quote_arg(x) for x in prog.command])))
+            return (prog.command, found)
+    return None
+
+def get_llvm_tool_names(tool: str) -> T.List[str]:
+    # Ordered list of possible suffixes of LLVM executables to try. Start with
+    # base, then try newest back to oldest (3.5 is arbitrary), and finally the
+    # devel version. Please note that the development snapshot in Debian does
+    # not have a distinct name. Do not move it to the beginning of the list
+    # unless it becomes a stable release.
+    suffixes = [
+        '', # base (no suffix)
+        '-21.1', '21.1',
+        '-21',  '21',
+        '-20.1', '20.1',
+        '-20',  '20',
+        '-19.1', '19.1',
+        '-19',  '19',
+        '-18.1', '18.1',
+        '-18',  '18',
+        '-17',  '17',
+        '-16',  '16',
+        '-15',  '15',
+        '-14',  '14',
+        '-13',  '13',
+        '-12',  '12',
+        '-11',  '11',
+        '-10',  '10',
+        '-9',   '90',
+        '-8',   '80',
+        '-7',   '70',
+        '-6.0', '60',
+        '-5.0', '50',
+        '-4.0', '40',
+        '-3.9', '39',
+        '-3.8', '38',
+        '-3.7', '37',
+        '-3.6', '36',
+        '-3.5', '35',
+        '-20',    # Debian development snapshot
+        '-devel', # FreeBSD development snapshot
+    ]
+    names: T.List[str] = []
+    for suffix in suffixes:
+        names.append(tool + suffix)
+    return names
+
+def detect_scanbuild() -> T.List[str]:
+    """ Look for scan-build binary on build platform
+
+    First, if a SCANBUILD env variable has been provided, give it precedence
+    on all platforms.
+
+    For most platforms, scan-build is found is the PATH contains a binary
+    named "scan-build". However, some distribution's package manager (FreeBSD)
+    don't. For those, loop through a list of candidates to see if one is
+    available.
+
+    Return: a single-element list of the found scan-build binary ready to be
+        passed to Popen()
+    """
+    exelist: T.List[str] = []
+    if 'SCANBUILD' in os.environ:
+        exelist = split_args(os.environ['SCANBUILD'])
+
+    else:
+        tools = get_llvm_tool_names('scan-build')
+        for tool in tools:
+            which = shutil.which(tool)
+            if which is not None:
+                exelist = [which]
+                break
+
+    if exelist:
+        tool = exelist[0]
+        if os.path.isfile(tool) and os.access(tool, os.X_OK):
+            return [tool]
+    return []
+
+def detect_clangformat() -> T.List[str]:
+    """ Look for clang-format binary on build platform
+
+    Do the same thing as detect_scanbuild to find clang-format except it
+    currently does not check the environment variable.
+
+    Return: a single-element list of the found clang-format binary ready to be
+        passed to Popen()
+    """
+    tools = get_llvm_tool_names('clang-format')
+    for tool in tools:
+        path = shutil.which(tool)
+        if path is not None:
+            return [path]
+    return []
+
+def detect_clangtidy() -> T.List[str]:
+    """ Look for clang-tidy binary on build platform
+
+    Return: a single-element list of the found clang-tidy binary ready to be
+        passed to Popen()
+    """
+    tools = get_llvm_tool_names('clang-tidy')
+    for tool in tools:
+        path = shutil.which(tool)
+        if path is not None:
+            return [path]
+    return []
+
+def detect_clangapply() -> T.List[str]:
+    """ Look for clang-apply-replacements binary on build platform
+
+    Return: a single-element list of the found clang-apply-replacements binary
+        ready to be passed to Popen()
+    """
+    tools = get_llvm_tool_names('clang-apply-replacements')
+    for tool in tools:
+        path = shutil.which(tool)
+        if path is not None:
+            return [path]
+    return []
diff --git a/run_mypy.py b/run_mypy.py
index 038e391b7..07f2c50a6 100755
--- a/run_mypy.py
+++ b/run_mypy.py
@@ -82,6 +82,7 @@ modules = [
     'mesonbuild/options.py',
     'mesonbuild/programs.py',
     'mesonbuild/rewriter.py',
+    'mesonbuild/tooldetect.py',
 ]
 additional = [
     'run_mypy.py',
diff --git a/run_tests.py b/run_tests.py
index 38c1e812b..05486713e 100755
--- a/run_tests.py
+++ b/run_tests.py
@@ -32,8 +32,9 @@ from mesonbuild import mesonlib
 from mesonbuild import mesonmain
 from mesonbuild import mtest
 from mesonbuild import mlog
-from mesonbuild.environment import Environment, detect_ninja
+from mesonbuild.environment import Environment
 from mesonbuild.envconfig import detect_machine_info
+from mesonbuild.tooldetect import detect_ninja
 from mesonbuild.coredata import version as meson_version
 from mesonbuild.options import backendlist
 from mesonbuild.mesonlib import setup_vsenv
diff --git a/test cases/unit/116 empty project/expected_mods.json b/test cases/unit/116 empty project/expected_mods.json
index defd6ea2f..e479bcbb7 100644
--- a/test cases/unit/116 empty project/expected_mods.json
+++ b/test cases/unit/116 empty project/expected_mods.json
@@ -231,6 +231,7 @@
       "mesonbuild.programs",
       "mesonbuild.scripts",
       "mesonbuild.scripts.meson_exe",
+      "mesonbuild.tooldetect",
       "mesonbuild.utils",
       "mesonbuild.utils.core",
       "mesonbuild.utils.platform",
@@ -239,6 +240,6 @@
       "mesonbuild.wrap",
       "mesonbuild.wrap.wrap"
     ],
-    "count": 70
+    "count": 71
   }
 }
diff --git a/unittests/allplatformstests.py b/unittests/allplatformstests.py
index 21cdaa8be..cf3427aeb 100644
--- a/unittests/allplatformstests.py
+++ b/unittests/allplatformstests.py
@@ -2497,7 +2497,7 @@ class AllPlatformTests(BasePlatformTests):
         self.assertIn('ERROR: compiler.has_header_symbol got unknown keyword arguments "prefixxx"', cm.exception.output)
 
     def test_templates(self):
-        ninja = mesonbuild.environment.detect_ninja()
+        ninja = mesonbuild.tooldetect.detect_ninja()
         if ninja is None:
             raise SkipTest('This test currently requires ninja. Fix this once "meson build" works.')
 
@@ -4290,14 +4290,14 @@ class AllPlatformTests(BasePlatformTests):
     def test_coverage(self):
         if mesonbuild.envconfig.detect_msys2_arch():
             raise SkipTest('Skipped due to problems with coverage on MSYS2')
-        gcovr_exe, gcovr_new_rootdir = mesonbuild.environment.detect_gcovr()
+        gcovr_exe, gcovr_new_rootdir = mesonbuild.tooldetect.detect_gcovr()
         if not gcovr_exe:
             raise SkipTest('gcovr not found, or too old')
         testdir = os.path.join(self.common_test_dir, '1 trivial')
         env = get_fake_env(testdir, self.builddir, self.prefix)
         cc = detect_c_compiler(env, MachineChoice.HOST)
         if cc.get_id() == 'clang':
-            if not mesonbuild.environment.detect_llvm_cov():
+            if not mesonbuild.tooldetect.detect_llvm_cov():
                 raise SkipTest('llvm-cov not found')
         if cc.get_id() == 'msvc':
             raise SkipTest('Test only applies to non-MSVC compilers')
@@ -4310,14 +4310,14 @@ class AllPlatformTests(BasePlatformTests):
     def test_coverage_complex(self):
         if mesonbuild.envconfig.detect_msys2_arch():
             raise SkipTest('Skipped due to problems with coverage on MSYS2')
-        gcovr_exe, gcovr_new_rootdir = mesonbuild.environment.detect_gcovr()
+        gcovr_exe, gcovr_new_rootdir = mesonbuild.tooldetect.detect_gcovr()
         if not gcovr_exe:
             raise SkipTest('gcovr not found, or too old')
         testdir = os.path.join(self.common_test_dir, '105 generatorcustom')
         env = get_fake_env(testdir, self.builddir, self.prefix)
         cc = detect_c_compiler(env, MachineChoice.HOST)
         if cc.get_id() == 'clang':
-            if not mesonbuild.environment.detect_llvm_cov():
+            if not mesonbuild.tooldetect.detect_llvm_cov():
                 raise SkipTest('llvm-cov not found')
         if cc.get_id() == 'msvc':
             raise SkipTest('Test only applies to non-MSVC compilers')
@@ -4330,14 +4330,14 @@ class AllPlatformTests(BasePlatformTests):
     def test_coverage_html(self):
         if mesonbuild.envconfig.detect_msys2_arch():
             raise SkipTest('Skipped due to problems with coverage on MSYS2')
-        gcovr_exe, gcovr_new_rootdir = mesonbuild.environment.detect_gcovr()
+        gcovr_exe, gcovr_new_rootdir = mesonbuild.tooldetect.detect_gcovr()
         if not gcovr_exe:
             raise SkipTest('gcovr not found, or too old')
         testdir = os.path.join(self.common_test_dir, '1 trivial')
         env = get_fake_env(testdir, self.builddir, self.prefix)
         cc = detect_c_compiler(env, MachineChoice.HOST)
         if cc.get_id() == 'clang':
-            if not mesonbuild.environment.detect_llvm_cov():
+            if not mesonbuild.tooldetect.detect_llvm_cov():
                 raise SkipTest('llvm-cov not found')
         if cc.get_id() == 'msvc':
             raise SkipTest('Test only applies to non-MSVC compilers')
@@ -4350,14 +4350,14 @@ class AllPlatformTests(BasePlatformTests):
     def test_coverage_text(self):
         if mesonbuild.envconfig.detect_msys2_arch():
             raise SkipTest('Skipped due to problems with coverage on MSYS2')
-        gcovr_exe, gcovr_new_rootdir = mesonbuild.environment.detect_gcovr()
+        gcovr_exe, gcovr_new_rootdir = mesonbuild.tooldetect.detect_gcovr()
         if not gcovr_exe:
             raise SkipTest('gcovr not found, or too old')
         testdir = os.path.join(self.common_test_dir, '1 trivial')
         env = get_fake_env(testdir, self.builddir, self.prefix)
         cc = detect_c_compiler(env, MachineChoice.HOST)
         if cc.get_id() == 'clang':
-            if not mesonbuild.environment.detect_llvm_cov():
+            if not mesonbuild.tooldetect.detect_llvm_cov():
                 raise SkipTest('llvm-cov not found')
         if cc.get_id() == 'msvc':
             raise SkipTest('Test only applies to non-MSVC compilers')
@@ -4370,14 +4370,14 @@ class AllPlatformTests(BasePlatformTests):
     def test_coverage_xml(self):
         if mesonbuild.envconfig.detect_msys2_arch():
             raise SkipTest('Skipped due to problems with coverage on MSYS2')
-        gcovr_exe, gcovr_new_rootdir = mesonbuild.environment.detect_gcovr()
+        gcovr_exe, gcovr_new_rootdir = mesonbuild.tooldetect.detect_gcovr()
         if not gcovr_exe:
             raise SkipTest('gcovr not found, or too old')
         testdir = os.path.join(self.common_test_dir, '1 trivial')
         env = get_fake_env(testdir, self.builddir, self.prefix)
         cc = detect_c_compiler(env, MachineChoice.HOST)
         if cc.get_id() == 'clang':
-            if not mesonbuild.environment.detect_llvm_cov():
+            if not mesonbuild.tooldetect.detect_llvm_cov():
                 raise SkipTest('llvm-cov not found')
         if cc.get_id() == 'msvc':
             raise SkipTest('Test only applies to non-MSVC compilers')
@@ -4390,14 +4390,14 @@ class AllPlatformTests(BasePlatformTests):
     def test_coverage_escaping(self):
         if mesonbuild.envconfig.detect_msys2_arch():
             raise SkipTest('Skipped due to problems with coverage on MSYS2')
-        gcovr_exe, gcovr_new_rootdir = mesonbuild.environment.detect_gcovr()
+        gcovr_exe, gcovr_new_rootdir = mesonbuild.tooldetect.detect_gcovr()
         if not gcovr_exe:
             raise SkipTest('gcovr not found, or too old')
         testdir = os.path.join(self.common_test_dir, '243 escape++')
         env = get_fake_env(testdir, self.builddir, self.prefix)
         cc = detect_c_compiler(env, MachineChoice.HOST)
         if cc.get_id() == 'clang':
-            if not mesonbuild.environment.detect_llvm_cov():
+            if not mesonbuild.tooldetect.detect_llvm_cov():
                 raise SkipTest('llvm-cov not found')
         if cc.get_id() == 'msvc':
             raise SkipTest('Test only applies to non-MSVC compilers')