Frontend: fix adjacent code blocks and test driver PYTHONPATH

frontend/Makefile

@@ -6,9 +6,9 @@ SPHINXCONF         = sphinx
 BUILDDIR           = dist
 SRC_TEST_DIR       = $(BUILDDIR)/test_output
 TEST_LAMBDA       ?= 0
-TEST_LOCAL_DRIVER  = PYTHONPATH="$PYTHONPATH:sphinx" python3 tests/compile_blocks.py --keep_files -B $(SRC_TEST_DIR)
+TEST_LOCAL_DRIVER  = PYTHONPATH="$$PYTHONPATH:sphinx" python3 tests/compile_blocks.py --keep_files -B $(SRC_TEST_DIR)
 TEST_OPTIONS      ?=
-TEST_LAMBDA_DRIVER = PYTHONPATH="$PYTHONPATH:sphinx" python3 tests/execute_rst_code_blocks.py --halt-on-failure
+TEST_LAMBDA_DRIVER = PYTHONPATH="$$PYTHONPATH:sphinx" python3 tests/execute_rst_code_blocks.py --halt-on-failure
 
 ifeq ($(strip $(TEST_LAMBDA)),1)
 TEST_DRIVER 	:= $(TEST_LAMBDA_DRIVER)

frontend/python/rst_code_example_pipeline/src/rst_code_example_pipeline/blocks.py

@@ -175,7 +175,12 @@ def start_config_block(i, line, indent):
 
             if cb_start != -1:
                 process_block(i, line, indent)
-            else:
+            # Not `else`: the line that ends a block (the first one indented
+            # less than its body) may itself start the next one.  A
+            # ``.. code::`` directly following a code block, with no prose
+            # between them, was otherwise consumed as the terminator and
+            # never seen as a directive, so the second block vanished.
+            if cb_start == -1:
                 if line[indent:].startswith(".. code::"):
                     start_code_block(i, line, indent)
                 elif line[indent:].startswith(":code-config:"):

frontend/python/rst_code_example_pipeline/tests/test_blocks.py

@@ -164,6 +164,56 @@ def test_active_defaults_to_true(self):
 # T-blocks-02: project and main_file attributes
 # ---------------------------------------------------------------------------
 
+class TestConsecutiveBlocks:
+    """A code block directly followed by another one, with no prose line
+    between them: both are parsed.  The line that terminates the first block
+    is the second block's directive, and it used to be consumed as the
+    terminator only, so the second block was silently dropped."""
+
+    RST = textwrap.dedent("""\
+        Intro.
+
+        .. code:: ada compile_button project=P.First
+
+            procedure First is begin null; end First;
+
+        .. code:: ada run_button project=P.Second
+
+            procedure Second is begin null; end Second;
+
+        Closing paragraph.
+        """)
+
+    def test_both_blocks_parsed(self):
+        blocks = [b for b in Block.get_blocks_from_rst(RST_FILE, self.RST)
+                  if isinstance(b, CodeBlock)]
+        assert [b.project for b in blocks] == ["P.First", "P.Second"]
+
+    def test_second_block_keeps_its_own_attributes(self):
+        blocks = [b for b in Block.get_blocks_from_rst(RST_FILE, self.RST)
+                  if isinstance(b, CodeBlock)]
+        assert blocks[1].buttons == ["run"]
+        assert blocks[1].text.strip() == "procedure Second is begin null; end Second;"
+
+    def test_block_after_an_indented_block(self):
+        rst = textwrap.dedent("""\
+            - item
+
+              .. code:: ada compile_button project=P.Nested
+
+                  procedure Nested is begin null; end Nested;
+
+            .. code:: ada compile_button project=P.Outer
+
+                procedure Outer is begin null; end Outer;
+
+            Closing paragraph.
+            """)
+        blocks = [b for b in Block.get_blocks_from_rst(RST_FILE, rst)
+                  if isinstance(b, CodeBlock)]
+        assert [b.project for b in blocks] == ["P.Nested", "P.Outer"]
+
+
 class TestProjectAndMainFile:
     RST = minimal_rst("""\
 .. code:: ada project=MyProject main=main.adb