cargo: Builder: Add support for "+", "+=", "if" and "foreach"

mesonbuild/cargo/builder.py

@@ -167,3 +167,45 @@ class Builder:
         block = mparser.CodeBlockNode(self._token('node', ''))
         block.lines = lines
         return block
+
+    def plus(self, lhs: mparser.BaseNode, rhs: mparser.BaseNode) -> mparser.ArithmeticNode:
+        """Create an addition node
+
+        :param lhs: The left of the addition
+        :param rhs: The right of the addition
+        :return: The ArithmeticNode
+        """
+        return mparser.ArithmeticNode('add', lhs, self._symbol('+'), rhs)
+
+    def plusassign(self, value: mparser.BaseNode, varname: str) -> mparser.PlusAssignmentNode:
+        """Create a "+=" node
+
+        :param value: The value to add
+        :param varname: The variable to assign
+        :return: The PlusAssignmentNode
+        """
+        return mparser.PlusAssignmentNode(self.identifier(varname), self._symbol('+='), value)
+
+    def if_(self, condition: mparser.BaseNode, block: mparser.CodeBlockNode) -> mparser.IfClauseNode:
+        """Create a "if" block
+
+        :param condition: The condition
+        :param block: Lines inside the condition
+        :return: The IfClauseNode
+        """
+        clause = mparser.IfClauseNode(condition)
+        clause.ifs.append(mparser.IfNode(clause, self._symbol('if'), condition, block))
+        clause.elseblock = mparser.EmptyNode(-1, -1, self.filename)
+        return clause
+
+    def foreach(self, varnames: T.List[str], items: mparser.BaseNode, block: mparser.CodeBlockNode) -> mparser.ForeachClauseNode:
+        """Create a "foreach" loop
+
+        :param varnames: Iterator variable names (one for list, two for dict).
+        :param items: The list of dict to iterate
+        :param block: Lines inside the loop
+        :return: The ForeachClauseNode
+        """
+        varids = [self.identifier(i) for i in varnames]
+        commas = [self._symbol(',') for i in range(len(varnames) - 1)]
+        return mparser.ForeachClauseNode(self._symbol('foreach'), varids, commas, self._symbol(':'), items, block, self._symbol('endforeach'))