Basic AST visitor pattern

4 files changed, 497 insertions, 0 deletions

diff --git a/mesonbuild/ast/__init__.py b/mesonbuild/ast/__init__.py
new file mode 100644
index 0000000..4b82d7e
--- /dev/null
+++ b/mesonbuild/ast/__init__.py
@@ -0,0 +1,25 @@
+# Copyright 2019 The Meson development team
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This class contains the basic functionality needed to run any interpreter
+# or an interpreter-based tool.
+
+__all__ = [
+    'AstInterpreter',
+    'RewriterInterpreter',
+    'AstVisitor'
+]
+
+from .interpreter import (AstInterpreter, RewriterInterpreter)
+from .visitor import AstVisitor
diff --git a/mesonbuild/ast/interpreter.py b/mesonbuild/ast/interpreter.py
new file mode 100644
index 0000000..c1068d4
--- /dev/null
+++ b/mesonbuild/ast/interpreter.py
@@ -0,0 +1,332 @@
+# Copyright 2016 The Meson development team
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This class contains the basic functionality needed to run any interpreter
+# or an interpreter-based tool.
+
+from .. import interpreterbase, mparser, mesonlib
+from .. import environment
+
+from ..interpreterbase import InterpreterException, InvalidArguments, BreakRequest, ContinueRequest
+
+import os, sys
+
+class DontCareObject(interpreterbase.InterpreterObject):
+    pass
+
+class MockExecutable(interpreterbase.InterpreterObject):
+    pass
+
+class MockStaticLibrary(interpreterbase.InterpreterObject):
+    pass
+
+class MockSharedLibrary(interpreterbase.InterpreterObject):
+    pass
+
+class MockCustomTarget(interpreterbase.InterpreterObject):
+    pass
+
+class MockRunTarget(interpreterbase.InterpreterObject):
+    pass
+
+ADD_SOURCE = 0
+REMOVE_SOURCE = 1
+
+class AstInterpreter(interpreterbase.InterpreterBase):
+    def __init__(self, source_root, subdir):
+        super().__init__(source_root, subdir)
+        self.visited_subdirs = {}
+        self.funcs.update({'project': self.func_do_nothing,
+                           'test': self.func_do_nothing,
+                           'benchmark': self.func_do_nothing,
+                           'install_headers': self.func_do_nothing,
+                           'install_man': self.func_do_nothing,
+                           'install_data': self.func_do_nothing,
+                           'install_subdir': self.func_do_nothing,
+                           'configuration_data': self.func_do_nothing,
+                           'configure_file': self.func_do_nothing,
+                           'find_program': self.func_do_nothing,
+                           'include_directories': self.func_do_nothing,
+                           'add_global_arguments': self.func_do_nothing,
+                           'add_global_link_arguments': self.func_do_nothing,
+                           'add_project_arguments': self.func_do_nothing,
+                           'add_project_link_arguments': self.func_do_nothing,
+                           'message': self.func_do_nothing,
+                           'generator': self.func_do_nothing,
+                           'error': self.func_do_nothing,
+                           'run_command': self.func_do_nothing,
+                           'assert': self.func_do_nothing,
+                           'subproject': self.func_do_nothing,
+                           'dependency': self.func_do_nothing,
+                           'get_option': self.func_do_nothing,
+                           'join_paths': self.func_do_nothing,
+                           'environment': self.func_do_nothing,
+                           'import': self.func_do_nothing,
+                           'vcs_tag': self.func_do_nothing,
+                           'add_languages': self.func_do_nothing,
+                           'declare_dependency': self.func_do_nothing,
+                           'files': self.func_do_nothing,
+                           'executable': self.func_do_nothing,
+                           'static_library': self.func_do_nothing,
+                           'shared_library': self.func_do_nothing,
+                           'library': self.func_do_nothing,
+                           'build_target': self.func_do_nothing,
+                           'custom_target': self.func_do_nothing,
+                           'run_target': self.func_do_nothing,
+                           'subdir': self.func_subdir,
+                           'set_variable': self.func_do_nothing,
+                           'get_variable': self.func_do_nothing,
+                           'is_variable': self.func_do_nothing,
+                           })
+
+    def func_do_nothing(self, node, args, kwargs):
+        return True
+
+    def func_subdir(self, node, args, kwargs):
+        args = self.flatten_args(args)
+        if len(args) != 1 or not isinstance(args[0], str):
+            sys.stderr.write('Unable to evaluate subdir({}) in AstInterpreter --> Skipping\n'.format(args))
+            return
+
+        prev_subdir = self.subdir
+        subdir = os.path.join(prev_subdir, args[0])
+        absdir = os.path.join(self.source_root, subdir)
+        buildfilename = os.path.join(self.subdir, environment.build_filename)
+        absname = os.path.join(self.source_root, buildfilename)
+        symlinkless_dir = os.path.realpath(absdir)
+        if symlinkless_dir in self.visited_subdirs:
+            sys.stderr.write('Trying to enter {} which has already been visited --> Skipping\n'.format(args[0]))
+            return
+        self.visited_subdirs[symlinkless_dir] = True
+
+        if not os.path.isfile(absname):
+            sys.stderr.write('Unable to find build file {} --> Skipping\n'.format(buildfilename))
+            return
+        with open(absname, encoding='utf8') as f:
+            code = f.read()
+        assert(isinstance(code, str))
+        try:
+            codeblock = mparser.Parser(code, self.subdir).parse()
+        except mesonlib.MesonException as me:
+            me.file = buildfilename
+            raise me
+
+        self.subdir = subdir
+        self.evaluate_codeblock(codeblock)
+        self.subdir = prev_subdir
+
+    def method_call(self, node):
+        return True
+
+    def evaluate_arithmeticstatement(self, cur):
+        return 0
+
+    def evaluate_plusassign(self, node):
+        return 0
+
+    def evaluate_indexing(self, node):
+        return 0
+
+    def unknown_function_called(self, func_name):
+        pass
+
+    def reduce_arguments(self, args):
+        assert(isinstance(args, mparser.ArgumentNode))
+        if args.incorrect_order():
+            raise InvalidArguments('All keyword arguments must be after positional arguments.')
+        return args.arguments, args.kwargs
+
+    def evaluate_comparison(self, node):
+        return False
+
+    def evaluate_foreach(self, node):
+        try:
+            self.evaluate_codeblock(node.block)
+        except ContinueRequest:
+            pass
+        except BreakRequest:
+            pass
+
+    def evaluate_if(self, node):
+        for i in node.ifs:
+            self.evaluate_codeblock(i.block)
+        if not isinstance(node.elseblock, mparser.EmptyNode):
+            self.evaluate_codeblock(node.elseblock)
+
+    def get_variable(self, varname):
+        return 0
+
+    def assignment(self, node):
+        pass
+
+    def flatten_args(self, args):
+        # Resolve mparser.ArrayNode if needed
+        flattend_args = []
+        if isinstance(args, mparser.ArrayNode):
+            args = [x.value for x in args.args.arguments]
+        for i in args:
+            if isinstance(i, mparser.ArrayNode):
+                flattend_args += [x.value for x in i.args.arguments]
+            elif isinstance(i, str):
+                flattend_args += [i]
+            else:
+                pass
+        return flattend_args
+
+class RewriterInterpreter(AstInterpreter):
+    def __init__(self, source_root, subdir):
+        super().__init__(source_root, subdir)
+        self.asts = {}
+        self.funcs.update({'files': self.func_files,
+                           'executable': self.func_executable,
+                           'static_library': self.func_static_lib,
+                           'shared_library': self.func_shared_lib,
+                           'library': self.func_library,
+                           'build_target': self.func_build_target,
+                           'custom_target': self.func_custom_target,
+                           'run_target': self.func_run_target,
+                           'subdir': self.func_subdir,
+                           'set_variable': self.func_set_variable,
+                           'get_variable': self.func_get_variable,
+                           'is_variable': self.func_is_variable,
+                           })
+
+    def func_executable(self, node, args, kwargs):
+        if args[0] == self.targetname:
+            if self.operation == ADD_SOURCE:
+                self.add_source_to_target(node, args, kwargs)
+            elif self.operation == REMOVE_SOURCE:
+                self.remove_source_from_target(node, args, kwargs)
+            else:
+                raise NotImplementedError('Bleep bloop')
+        return MockExecutable()
+
+    def func_static_lib(self, node, args, kwargs):
+        return MockStaticLibrary()
+
+    def func_shared_lib(self, node, args, kwargs):
+        return MockSharedLibrary()
+
+    def func_library(self, node, args, kwargs):
+        return self.func_shared_lib(node, args, kwargs)
+
+    def func_custom_target(self, node, args, kwargs):
+        return MockCustomTarget()
+
+    def func_run_target(self, node, args, kwargs):
+        return MockRunTarget()
+
+    def func_subdir(self, node, args, kwargs):
+        prev_subdir = self.subdir
+        subdir = os.path.join(prev_subdir, args[0])
+        self.subdir = subdir
+        buildfilename = os.path.join(self.subdir, environment.build_filename)
+        absname = os.path.join(self.source_root, buildfilename)
+        if not os.path.isfile(absname):
+            self.subdir = prev_subdir
+            raise InterpreterException('Nonexistent build def file %s.' % buildfilename)
+        with open(absname, encoding='utf8') as f:
+            code = f.read()
+        assert(isinstance(code, str))
+        try:
+            codeblock = mparser.Parser(code, self.subdir).parse()
+            self.asts[subdir] = codeblock
+        except mesonlib.MesonException as me:
+            me.file = buildfilename
+            raise me
+        try:
+            self.evaluate_codeblock(codeblock)
+        except SubdirDoneRequest:
+            pass
+        self.subdir = prev_subdir
+
+    def func_files(self, node, args, kwargs):
+        if not isinstance(args, list):
+            return [args]
+        return args
+
+    def transform(self):
+        self.load_root_meson_file()
+        self.asts[''] = self.ast
+        self.sanity_check_ast()
+        self.parse_project()
+        self.run()
+
+    def add_source(self, targetname, filename):
+        self.operation = ADD_SOURCE
+        self.targetname = targetname
+        self.filename = filename
+        self.transform()
+
+    def remove_source(self, targetname, filename):
+        self.operation = REMOVE_SOURCE
+        self.targetname = targetname
+        self.filename = filename
+        self.transform()
+
+    def add_source_to_target(self, node, args, kwargs):
+        namespan = node.args.arguments[0].bytespan
+        buildfilename = os.path.join(self.source_root, self.subdir, environment.build_filename)
+        raw_data = open(buildfilename, 'r').read()
+        updated = raw_data[0:namespan[1]] + (", '%s'" % self.filename) + raw_data[namespan[1]:]
+        open(buildfilename, 'w').write(updated)
+        sys.exit(0)
+
+    def remove_argument_item(self, args, i):
+        assert(isinstance(args, mparser.ArgumentNode))
+        namespan = args.arguments[i].bytespan
+        # Usually remove the comma after this item but if it is
+        # the last argument, we need to remove the one before.
+        if i >= len(args.commas):
+            i -= 1
+        if i < 0:
+            commaspan = (0, 0) # Removed every entry in the list.
+        else:
+            commaspan = args.commas[i].bytespan
+        if commaspan[0] < namespan[0]:
+            commaspan, namespan = namespan, commaspan
+        buildfilename = os.path.join(self.source_root, args.subdir, environment.build_filename)
+        raw_data = open(buildfilename, 'r').read()
+        intermediary = raw_data[0:commaspan[0]] + raw_data[commaspan[1]:]
+        updated = intermediary[0:namespan[0]] + intermediary[namespan[1]:]
+        open(buildfilename, 'w').write(updated)
+        sys.exit(0)
+
+    def hacky_find_and_remove(self, node_to_remove):
+        for a in self.asts[node_to_remove.subdir].lines:
+            if a.lineno == node_to_remove.lineno:
+                if isinstance(a, mparser.AssignmentNode):
+                    v = a.value
+                    if not isinstance(v, mparser.ArrayNode):
+                        raise NotImplementedError('Not supported yet, bro.')
+                    args = v.args
+                    for i in range(len(args.arguments)):
+                        if isinstance(args.arguments[i], mparser.StringNode) and self.filename == args.arguments[i].value:
+                            self.remove_argument_item(args, i)
+                raise NotImplementedError('Sukkess')
+
+    def remove_source_from_target(self, node, args, kwargs):
+        for i in range(1, len(node.args)):
+            # Is file name directly in function call as a string.
+            if isinstance(node.args.arguments[i], mparser.StringNode) and self.filename == node.args.arguments[i].value:
+                self.remove_argument_item(node.args, i)
+            # Is file name in a variable that gets expanded here.
+            if isinstance(node.args.arguments[i], mparser.IdNode):
+                avar = self.get_variable(node.args.arguments[i].value)
+                if not isinstance(avar, list):
+                    raise NotImplementedError('Non-arrays not supported yet, sorry.')
+                for entry in avar:
+                    if isinstance(entry, mparser.StringNode) and entry.value == self.filename:
+                        self.hacky_find_and_remove(entry)
+        sys.exit('Could not find source %s in target %s.' % (self.filename, args[0]))
diff --git a/mesonbuild/ast/printer.py b/mesonbuild/ast/printer.py
new file mode 100644
index 0000000..c1710be
--- /dev/null
+++ b/mesonbuild/ast/printer.py
@@ -0,0 +1,22 @@
+# Copyright 2018 The Meson development team
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This class contains the basic functionality needed to run any interpreter
+# or an interpreter-based tool
+
+from . import AstVisitor
+
+class AstPrinter(AstVisitor):
+    def __init__(self):
+        pass
diff --git a/mesonbuild/ast/visitor.py b/mesonbuild/ast/visitor.py
new file mode 100644
index 0000000..487cd5b
--- /dev/null
+++ b/mesonbuild/ast/visitor.py
@@ -0,0 +1,118 @@
+# Copyright 2018 The Meson development team
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This class contains the basic functionality needed to run any interpreter
+# or an interpreter-based tool
+
+from .. import mparser
+
+class AstVisitor:
+    def __init__(self):
+        pass
+
+    def visit_BooleanNode(self, node: mparser.BooleanNode):
+        pass
+
+    def visit_IdNode(self, node: mparser.IdNode):
+        pass
+
+    def visit_NumberNode(self, node: mparser.NumberNode):
+        pass
+
+    def visit_StringNode(self, node: mparser.StringNode):
+        pass
+
+    def visit_ContinueNode(self, node: mparser.ContinueNode):
+        pass
+
+    def visit_BreakNode(self, node: mparser.BreakNode):
+        pass
+
+    def visit_ArrayNode(self, node: mparser.ArrayNode):
+        node.args.accept(self)
+
+    def visit_DictNode(self, node: mparser.DictNode):
+        node.args.accept(self)
+
+    def visit_EmptyNode(self, node: mparser.EmptyNode):
+        pass
+
+    def visit_OrNode(self, node: mparser.OrNode):
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_AndNode(self, node: mparser.AndNode):
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_ComparisonNode(self, node: mparser.ComparisonNode):
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_ArithmeticNode(self, node: mparser.ArithmeticNode):
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_NotNode(self, node: mparser.NotNode):
+        node.value.accept(self)
+
+    def visit_CodeBlockNode(self, node: mparser.CodeBlockNode):
+        for i in node.lines:
+            i.accept(self)
+
+    def visit_IndexNode(self, node: mparser.IndexNode):
+        node.index.accept(self)
+
+    def visit_MethodNode(self, node: mparser.MethodNode):
+        node.source_object.accept(self)
+        node.args.accept(self)
+
+    def visit_FunctionNode(self, node: mparser.FunctionNode):
+        node.args.accept(self)
+
+    def visit_AssignmentNode(self, node: mparser.AssignmentNode):
+        node.value.accept(self)
+
+    def visit_PlusAssignmentNode(self, node: mparser.PlusAssignmentNode):
+        node.value.accept(self)
+
+    def visit_ForeachClauseNode(self, node: mparser.ForeachClauseNode):
+        node.items.accept(self)
+        node.block.accept(self)
+
+    def visit_IfClauseNode(self, node: mparser.IfClauseNode):
+        for i in node.ifs:
+            i.accept(self)
+        if node.elseblock:
+            node.elseblock.accept(self)
+
+    def visit_UMinusNode(self, node: mparser.UMinusNode):
+        node.value.accept(self)
+
+    def visit_IfNode(self, node: mparser.IfNode):
+        node.condition.accept(self)
+        node.block.accept(self)
+
+    def visit_TernaryNode(self, node: mparser.TernaryNode):
+        node.condition.accept(self)
+        node.trueblock.accept(self)
+        node.falseblock.accept(self)
+
+    def visit_ArgumentNode(self, node: mparser.ArgumentNode):
+        for i in node.arguments:
+            i.accept(self)
+        for i in node.commas:
+            pass
+        for val in node.kwargs.values():
+            val.accept(self)