[docs] Remove empty code blocks

This fixes some of the issues highlighted in apache#13668, the parser that
checks to ensure that the hidden import is placed in the right spot was
incorrect, this includes some fixes to get it working for the cases in
that issue.

gallery/how_to/compile_models/from_darknet.py

@@ -31,13 +31,12 @@
   pip install opencv-python
 """
 
+# numpy and matplotlib
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
-
-# numpy and matplotlib
 import numpy as np
 import matplotlib.pyplot as plt
 import sys

gallery/how_to/compile_models/from_tensorflow.py

@@ -24,13 +24,12 @@
 Please refer to https://www.tensorflow.org/install
 """
 
+# tvm, relay
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
-
-# tvm, relay
 import tvm
 from tvm import te
 from tvm import relay

gallery/how_to/deploy_models/deploy_prequantized.py

@@ -28,14 +28,15 @@
 Once loaded, we can run compiled, quantized models on any hardware TVM supports.
 """
 
+#################################################################################
+# First, necessary imports
+
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
 
-#################################################################################
-# First, necessary imports
 from PIL import Image
 
 import numpy as np

gallery/how_to/deploy_models/deploy_prequantized_tflite.py

@@ -42,15 +42,16 @@
 
 """
 
+###############################################################################
+# Necessary imports
+# -----------------
+
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
 
-###############################################################################
-# Necessary imports
-# -----------------
 import os
 
 import numpy as np

gallery/how_to/deploy_models/deploy_sparse.py

@@ -70,17 +70,18 @@
 sparse speed using fake weights to see the benefit of structured sparsity.
 """
 
+###############################################################################
+# Load Required Modules
+# ---------------------
+# Other than TVM, scipy, the latest transformers, and
+# tensorflow 2.2+ are required.
+
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
 
-###############################################################################
-# Load Required Modules
-# ---------------------
-# Other than TVM, scipy, the latest transformers, and
-# tensorflow 2.2+ are required.
 import os
 import tvm
 import time

gallery/how_to/extend_tvm/bring_your_own_datatypes.py

@@ -52,17 +52,18 @@
     ctypes.CDLL('my-datatype-lib.so', ctypes.RTLD_GLOBAL)
 """
 
+######################
+# A Simple TVM Program
+# --------------------
+#
+# We'll begin by writing a simple program in TVM; afterwards, we will re-write it to use custom datatypes.
+
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
 
-######################
-# A Simple TVM Program
-# --------------------
-#
-# We'll begin by writing a simple program in TVM; afterwards, we will re-write it to use custom datatypes.
 import tvm
 from tvm import relay
 

gallery/how_to/optimize_operators/opt_conv_cuda.py

@@ -30,12 +30,6 @@
 
 """
 
-# sphinx_gallery_start_ignore
-from tvm import testing
-
-testing.utils.install_request_hook(depth=3)
-# sphinx_gallery_end_ignore
-
 ################################################################
 # Preparation and Algorithm
 # -------------------------
@@ -44,7 +38,12 @@
 # dimensions. The batch size is 256. Convolution filters contain 512 filters
 # of size 3 x 3.  We use stride size 1 and padding size 1 for the
 # convolution. The following code defines the convolution algorithm in TVM.
-#
+
+# sphinx_gallery_start_ignore
+from tvm import testing
+
+testing.utils.install_request_hook(depth=3)
+# sphinx_gallery_end_ignore
 
 import numpy as np
 import tvm

gallery/how_to/optimize_operators/opt_gemm.py

@@ -48,19 +48,19 @@
 Intel i7-4770HQ CPU. The cache line size should be 64 bytes for all the x86 CPUs.
 """
 
-# sphinx_gallery_start_ignore
-from tvm import testing
-
-testing.utils.install_request_hook(depth=3)
-# sphinx_gallery_end_ignore
-
 ################################################################################################
 # Preparation and Baseline
 # ------------------------
 # In this tutorial, we will demo how to use TVM to optimize matrix multiplication.
 # Before actually demonstrating, we first define these variables.
 # Then we write a baseline implementation, the simplest way to write a matrix multiplication in TVM.
 
+# sphinx_gallery_start_ignore
+from tvm import testing
+
+testing.utils.install_request_hook(depth=3)
+# sphinx_gallery_end_ignore
+
 import tvm
 import tvm.testing
 from tvm import te

gallery/how_to/work_with_pytorch/using_as_torch.py

@@ -24,13 +24,12 @@
 Using the decorator `as_torch`, users can wrap TVMScript code into a PyTorch nn.Module naturally.
 """
 
+# Import PyTorch, as well as necessary libraries
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
-
-# Import PyTorch, as well as necessary libraries
 import torch
 import torch.nn.functional as F
 import torch.utils.benchmark as benchmark

gallery/how_to/work_with_pytorch/using_optimized_torch.py

@@ -24,13 +24,12 @@
 To follow this tutorial, PyTorch, as well as TorchVision, should be installed.
 """
 
+# Import PyTorch
 # sphinx_gallery_start_ignore
 from tvm import testing
 
 testing.utils.install_request_hook(depth=3)
 # sphinx_gallery_end_ignore
-
-# Import PyTorch
 import torch
 import torch.nn as nn
 import torch.nn.functional as F

gallery/tutorial/autotvm_relay_x86.py

@@ -42,12 +42,6 @@
 how to use them through the Python API.
 """
 
-# sphinx_gallery_start_ignore
-from tvm import testing
-
-testing.utils.install_request_hook(depth=3)
-# sphinx_gallery_end_ignore
-
 ################################################################################
 # TVM is a deep learning compiler framework, with a number of different modules
 # available for working with deep learning models and operators. In this
@@ -60,6 +54,12 @@
 # and post-processing of the image data, the TVM Relay framework, and the TVM
 # Graph Executor.
 
+# sphinx_gallery_start_ignore
+from tvm import testing
+
+testing.utils.install_request_hook(depth=3)
+# sphinx_gallery_end_ignore
+
 import onnx
 from tvm.contrib.download import download_testdata
 from PIL import Image

gallery/tutorial/relay_quick_start.py

@@ -26,12 +26,6 @@
 Notice that you need to build TVM with cuda and llvm enabled.
 """
 
-# sphinx_gallery_start_ignore
-from tvm import testing
-
-testing.utils.install_request_hook(depth=3)
-# sphinx_gallery_end_ignore
-
 ######################################################################
 # Overview for Supported Hardware Backend of TVM
 # ----------------------------------------------
@@ -43,6 +37,12 @@
 # In this tutorial, we'll choose cuda and llvm as target backends.
 # To begin with, let's import Relay and TVM.
 
+# sphinx_gallery_start_ignore
+from tvm import testing
+
+testing.utils.install_request_hook(depth=3)
+# sphinx_gallery_end_ignore
+
 import numpy as np
 
 from tvm import relay

gallery/tutorial/tensor_expr_get_started.py

@@ -39,12 +39,6 @@
 features of TVM.
 """
 
-# sphinx_gallery_start_ignore
-from tvm import testing
-
-testing.utils.install_request_hook(depth=3)
-# sphinx_gallery_end_ignore
-
 ################################################################################
 # Example 1: Writing and Scheduling Vector Addition in TE for CPU
 # ---------------------------------------------------------------
@@ -53,6 +47,12 @@
 # vector addition, followed by a schedule targeted towards a CPU.
 # We begin by initializing a TVM environment.
 
+# sphinx_gallery_start_ignore
+from tvm import testing
+
+testing.utils.install_request_hook(depth=3)
+# sphinx_gallery_end_ignore
+
 import tvm
 import tvm.testing
 from tvm import te

tests/lint/check_request_hook.py

@@ -41,19 +41,24 @@ def find_code_block_line(lines: List[str]) -> Optional[int]:
     """
     in_multiline_string = False
     in_sphinx_directive = False
+    in_standalone_comment = True
 
     i = 0
     lines = lines[APACHE_HEADER_LINES:]
     while i < len(lines):
         line = lines[i].strip()
+        in_comment = False
         if '"""' in line:
             in_multiline_string = not in_multiline_string
         elif "# sphinx_gallery_" in line:
             in_sphinx_directive = not in_sphinx_directive
-        elif line.startswith("#") or in_sphinx_directive or in_multiline_string or line == "":
+        elif line.startswith("##") or in_sphinx_directive or in_multiline_string or line == "":
+            in_standalone_comment = False
+            pass
+        elif line.startswith("#") and not in_standalone_comment:
             pass
         else:
-            return i
+            return i + APACHE_HEADER_LINES
         i += 1
 
     return None
@@ -69,7 +74,6 @@ def find_code_block_line(lines: List[str]) -> Optional[int]:
     args = parser.parse_args()
 
     gallery_files = (REPO_ROOT / "gallery").glob("**/*.py")
-    # gallery_files = [x for x in gallery_files if "cross_compi" in str(x)]
 
     errors = []
     for file in gallery_files: