[TVMSCRIPT] Using diagnostics for TVM Script (#6797)

* [TVMSCRIPT] Using diagnostics for TVM Script

* fix lint

* More documentation, improve some error messages

* Apply suggestions from code review

Co-authored-by: Leandro Nunes <leandron85@gmail.com>

* Add synr to ci setup and setup.py

* remove typed_ast dependency

Co-authored-by: Leandro Nunes <leandron85@gmail.com>

docker/install/ubuntu_install_python_package.sh

@@ -21,4 +21,4 @@ set -u
 set -o pipefail
 
 # install libraries for python package on ubuntu
-pip3 install six numpy pytest cython decorator scipy tornado typed_ast pytest pytest-xdist pytest-profiling mypy orderedset attrs requests Pillow packaging cloudpickle synr
+pip3 install six numpy pytest cython decorator scipy tornado pytest pytest-xdist pytest-profiling mypy orderedset attrs requests Pillow packaging cloudpickle synr

python/setup.py

@@ -183,7 +183,7 @@ def get_package_data_files():
         "decorator",
         "attrs",
         "psutil",
-        "typed_ast",
+        "synr>=0.2.1",
     ],
     extras_require={
         "test": ["pillow<7", "matplotlib"],

python/tvm/script/context_maintainer.py

@@ -70,5 +70,5 @@ def lookup_symbol(self, name):
                 return symbols[name]
         return None
 
-    def report_error(self, message):
-        self.parser.report_error(message)
+    def report_error(self, message, span):
+        self.parser.report_error(message, span)

python/tvm/script/diagnostics.py

@@ -0,0 +1,54 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+"""Bridge from synr's (the library used for parsing the python AST)
+   DiagnosticContext to TVM's diagnostics
+"""
+import tvm
+from synr import DiagnosticContext, ast
+from tvm.ir.diagnostics import DiagnosticContext as TVMCtx
+from tvm.ir.diagnostics import get_renderer, DiagnosticLevel, Diagnostic
+
+
+class TVMDiagnosticCtx(DiagnosticContext):
+    """TVM diagnostics for synr"""
+
+    diag_ctx: TVMCtx
+
+    def __init__(self) -> None:
+        self.diag_ctx = TVMCtx(tvm.IRModule(), get_renderer())
+        self.source_name = None
+
+    def to_tvm_span(self, src_name, ast_span: ast.Span) -> tvm.ir.Span:
+        return tvm.ir.Span(
+            src_name,
+            ast_span.start_line,
+            ast_span.end_line,
+            ast_span.start_column,
+            ast_span.end_column,
+        )
+
+    def add_source(self, name: str, source: str) -> None:
+        src_name = self.diag_ctx.module.source_map.add(name, source)
+        self.source_name = src_name
+
+    def emit(self, _level, message, span):
+        span = self.to_tvm_span(self.source_name, span)
+        self.diag_ctx.emit(Diagnostic(DiagnosticLevel.ERROR, span, message))
+        self.diag_ctx.render()  # Raise exception on the first error we hit. TODO remove
+
+    def render(self):
+        self.diag_ctx.render()

python/tvm/script/meta_unparser.py

@@ -17,34 +17,29 @@
 """Unparse meta AST node into a dict"""
 # pylint: disable=invalid-name
 
-from typed_ast import ast3 as ast
+from synr import Transformer
 
 
-class MetaUnparser(ast.NodeVisitor):
+class MetaUnparser(Transformer):
     """Python AST Visitor to unparse meta AST node into a dict"""
 
-    def visit_Dict(self, node):
+    def transform(self, node):
+        method = "transform_" + node.__class__.__name__
+        visitor = getattr(self, method, None)
+        if visitor is None:
+            self.error(f"Unexpected node type {type(node)} when parsing __tvm_meta__", node.span)
+        return visitor(node)
+
+    def transform_DictLiteral(self, node):
         keys = [self.visit(key) for key in node.keys]
         values = [self.visit(value) for value in node.values]
         return dict(zip(keys, values))
 
-    def visit_Tuple(self, node):
+    def transform_Tuple(self, node):
         return tuple(self.visit(element) for element in node.elts)
 
-    def visit_List(self, node):
+    def transform_ArrayLiteral(self, node):
         return [self.visit(element) for element in node.elts]
 
-    def visit_keyword(self, node):
-        return node.arg, self.visit(node.value)
-
-    def visit_NameConstant(self, node):
-        return node.value
-
-    def visit_Constant(self, node):
+    def transform_Constant(self, node):
         return node.value
-
-    def visit_Num(self, node):
-        return node.n
-
-    def visit_Str(self, node):
-        return node.s