intrp: Don't do custom AST parsing for project()

Reuse the standard evaluate_codeblock() parsing since it does proper
error handling, and also handles, for instance, lists in string
arguments (flatten), etc. properly.

We need to declare more variables in advance now, but that should be ok.

mesonbuild/interpreter.py

@@ -1129,6 +1129,12 @@ class Interpreter():
         self.sanity_check_ast()
         self.variables = {}
         self.builtin = {}
+        self.generators = []
+        self.visited_subdirs = {}
+        self.global_args_frozen = False
+        self.subprojects = {}
+        self.subproject_stack = []
+        self.build_func_dict()
         self.parse_project()
         self.builtin['build_machine'] = BuildMachine(self.coredata.compilers)
         if not self.build.environment.is_cross_build():
@@ -1145,13 +1151,7 @@ class Interpreter():
             else:
                 self.builtin['target_machine'] = self.builtin['host_machine']
         self.builtin['meson'] = MesonMain(build, self)
-        self.build_func_dict()
         self.build_def_files = [os.path.join(self.subdir, environment.build_filename)]
-        self.generators = []
-        self.visited_subdirs = {}
-        self.global_args_frozen = False
-        self.subprojects = {}
-        self.subproject_stack = []
 
     def build_func_dict(self):
         self.funcs = {'project' : self.func_project,
@@ -1203,9 +1203,7 @@ class Interpreter():
         Parses project() and initializes languages, compilers etc. Do this
         early because we need this before we parse the rest of the AST.
         """
-        project = self.ast.lines[0]
-        args, kwargs = self.reduce_arguments(project.args)
-        self.func_project(project, args, kwargs)
+        self.evaluate_codeblock(self.ast, end=1)
 
     def module_method_callback(self, invalues):
         unwrap_single = False
@@ -1282,7 +1280,7 @@ class Interpreter():
         self.evaluate_codeblock(self.ast, start=1)
         mlog.log('Build targets in project:', mlog.bold(str(len(self.build.targets))))
 
-    def evaluate_codeblock(self, node, start=0):
+    def evaluate_codeblock(self, node, start=0, end=None):
         if node is None:
             return
         if not isinstance(node, mparser.CodeBlockNode):
@@ -1290,8 +1288,8 @@ class Interpreter():
             e.lineno = node.lineno
             e.colno = node.colno
             raise e
-        statements = node.lines
-        i = start
+        statements = node.lines[start:end]
+        i = 0
         while i < len(statements):
             cur = statements[i]
             try: