holders: Move get_version from directly to ExternalProgram

1 files changed, 22 insertions, 1 deletions

diff --git a/mesonbuild/programs.py b/mesonbuild/programs.py
index 06af320..bb14f96 100644
--- a/mesonbuild/programs.py
+++ b/mesonbuild/programs.py
@@ -19,6 +19,7 @@ import os
 import shutil
 import stat
 import sys
+import re
 import typing as T
 from pathlib import Path
 
@@ -28,6 +29,7 @@ from .mesonlib import MachineChoice
 
 if T.TYPE_CHECKING:
     from .environment import Environment
+    from .interpreter import Interpreter
 
 
 class ExternalProgram(mesonlib.HoldableObject):
@@ -41,7 +43,8 @@ class ExternalProgram(mesonlib.HoldableObject):
                  silent: bool = False, search_dir: T.Optional[str] = None,
                  extra_search_dirs: T.Optional[T.List[str]] = None):
         self.name = name
-        self.path = None  # type: T.Optional[str]
+        self.path: T.Optional[str] = None
+        self.cached_version: T.Optional[str] = None
         if command is not None:
             self.command = mesonlib.listify(command)
             if mesonlib.is_windows():
@@ -97,6 +100,24 @@ class ExternalProgram(mesonlib.HoldableObject):
         '''Human friendly description of the command'''
         return ' '.join(self.command)
 
+    def get_version(self, interpreter: 'Interpreter') -> str:
+        if not self.cached_version:
+            raw_cmd = self.get_command() + ['--version']
+            cmd: T.List[T.Union[str, ExternalProgram]] = [self, '--version']
+            res = interpreter.run_command_impl(interpreter.current_node, cmd, {}, True)
+            if res.returncode != 0:
+                m = 'Running {!r} failed'
+                raise mesonlib.MesonException(m.format(raw_cmd))
+            output = res.stdout.strip()
+            if not output:
+                output = res.stderr.strip()
+            match = re.search(r'([0-9][0-9\.]+)', output)
+            if not match:
+                m = 'Could not find a version number in output of {!r}'
+                raise mesonlib.MesonException(m.format(raw_cmd))
+            self.cached_version = match.group(1)
+        return self.cached_version
+
     @classmethod
     def from_bin_list(cls, env: 'Environment', for_machine: MachineChoice, name: str) -> 'ExternalProgram':
         # There is a static `for_machine` for this class because the binary