Allow meson build file to exit early. (#2808)

2 files changed, 15 insertions, 1 deletions

diff --git a/mesonbuild/interpreter.py b/mesonbuild/interpreter.py
index c87a49b..7dbf1cc 100644
--- a/mesonbuild/interpreter.py
+++ b/mesonbuild/interpreter.py
@@ -26,7 +26,7 @@ from .dependencies import ExternalProgram
 from .dependencies import InternalDependency, Dependency, DependencyException
 from .interpreterbase import InterpreterBase
 from .interpreterbase import check_stringlist, noPosargs, noKwargs, stringArgs, permittedKwargs, permittedMethodKwargs
-from .interpreterbase import InterpreterException, InvalidArguments, InvalidCode
+from .interpreterbase import InterpreterException, InvalidArguments, InvalidCode, SubdirDoneRequest
 from .interpreterbase import InterpreterObject, MutableInterpreterObject, Disabler
 from .modules import ModuleReturnValue
 
@@ -1612,6 +1612,7 @@ class Interpreter(InterpreterBase):
                            'static_library': self.func_static_lib,
                            'test': self.func_test,
                            'vcs_tag': self.func_vcs_tag,
+                           'subdir_done': self.func_subdir_done,
                            })
         if 'MESON_UNIT_TEST' in os.environ:
             self.funcs.update({'exception': self.func_exception})
@@ -2607,6 +2608,14 @@ root and issuing %s.
         return self.func_custom_target(node, [kwargs['output']], kwargs)
 
     @stringArgs
+    def func_subdir_done(self, node, args, kwargs):
+        if len(kwargs) > 0:
+            raise InterpreterException('exit does not take named arguments')
+        if len(args) > 0:
+            raise InterpreterException('exit does not take any arguments')
+        raise SubdirDoneRequest()
+
+    @stringArgs
     @permittedKwargs(permitted_kwargs['custom_target'])
     def func_custom_target(self, node, args, kwargs):
         if len(args) != 1:
diff --git a/mesonbuild/interpreterbase.py b/mesonbuild/interpreterbase.py
index 9279506..f957d90 100644
--- a/mesonbuild/interpreterbase.py
+++ b/mesonbuild/interpreterbase.py
@@ -105,6 +105,9 @@ class InvalidCode(InterpreterException):
 class InvalidArguments(InterpreterException):
     pass
 
+class SubdirDoneRequest(BaseException):
+    pass
+
 class InterpreterObject:
     def __init__(self):
         self.methods = {}
@@ -203,6 +206,8 @@ class InterpreterBase:
             try:
                 self.current_lineno = cur.lineno
                 self.evaluate_statement(cur)
+            except SubdirDoneRequest:
+                break
             except Exception as e:
                 if not(hasattr(e, 'lineno')):
                     e.lineno = cur.lineno