Interpreter: Fix subdir_done() to exit from inside if/foreach blocks

Closes: #3700.

mesonbuild/interpreter.py

@@ -3128,7 +3128,10 @@ root and issuing %s.
         except mesonlib.MesonException as me:
             me.file = buildfilename
             raise me
-        self.evaluate_codeblock(codeblock)
+        try:
+            self.evaluate_codeblock(codeblock)
+        except SubdirDoneRequest:
+            pass
         self.subdir = prev_subdir
 
     def _get_kwarg_install_mode(self, kwargs):

mesonbuild/interpreterbase.py

@@ -326,7 +326,10 @@ class InterpreterBase:
     def run(self):
         # Evaluate everything after the first line, which is project() because
         # we already parsed that in self.parse_project()
-        self.evaluate_codeblock(self.ast, start=1)
+        try:
+            self.evaluate_codeblock(self.ast, start=1)
+        except SubdirDoneRequest:
+            pass
 
     def evaluate_codeblock(self, node, start=0, end=None):
         if node is None:
@@ -343,8 +346,6 @@ 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

test cases/common/188 subdir_done/meson.build

@@ -3,7 +3,9 @@
 
 project('example exit', 'cpp')
 
-subdir_done()
+if true
+  subdir_done()
+endif
 
 executable('main', 'main.cpp')
 error('Unreachable')