From c131f6e3b29daf8e0bece58d5b77783d5bde86c6 Mon Sep 17 00:00:00 2001
From: Tim Hunter <tjhunter@cs.stanford.edu>
Date: Sun, 7 Mar 2021 14:34:45 +0100
Subject: [PATCH 1/2] tests that show issue

---
 dds/_introspect_indirect.py |  3 ++-
 dds/introspect.py           | 16 +++++++++++++---
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/dds/_introspect_indirect.py b/dds/_introspect_indirect.py
index f3c2b14..5ae60b3 100644
--- a/dds/_introspect_indirect.py
+++ b/dds/_introspect_indirect.py
@@ -29,6 +29,7 @@
     ExternalVarsVisitor,
     LocalVar,
     _function_name,
+    read_source,
 )
 from .structures import (
     FunctionArgContext,
@@ -126,7 +127,7 @@ def _introspect_fun(
         fiis_ = gctx.cached_indirect_interactions.get(fun_path)
         if fiis_ is not None:
             return fiis_
-        src = inspect.getsource(f)
+        src = read_source(f)
         # _logger.debug(f"Starting _introspect: {f}: src={src}")
         ast_src = ast.parse(src)
         ast_f = ast_src.body[0]  # type: ignore
diff --git a/dds/introspect.py b/dds/introspect.py
index 007592c..df8b99f 100644
--- a/dds/introspect.py
+++ b/dds/introspect.py
@@ -106,7 +106,7 @@ def _introspect_class(
     fis_ = gctx.cached_fun_interactions.get(fis_key)
     if fis_ is not None:
         return fis_
-    src = inspect.getsource(c)
+    src = read_source(c)
     # _logger.debug(f"Starting _introspect_class: {c}: src={src}")
     ast_src = ast.parse(src)
     ast_f: ast.ClassDef = ast_src.body[0]  # type: ignore
@@ -191,7 +191,7 @@ def _introspect_fun(
     ast_f: Union[ast.Lambda, ast.FunctionDef]
     if is_lambda(f):
         # _logger.debug(f"_introspect: is_lambda: {f}")
-        src = inspect.getsource(f)
+        src = read_source(f)
         h = dds_hash(src)
         # Have a stable name for the lambda function
         fun_path = CanonicalPath(
@@ -211,7 +211,7 @@ def _introspect_fun(
         fis_ = gctx.cached_fun_interactions.get(fis_key)
         if fis_ is not None:
             return fis_
-        src = inspect.getsource(f)
+        src = read_source(f)
         # _logger.debug(f"Starting _introspect: {f}: src={src}")
         ast_src = ast.parse(src)
         ast_f = ast_src.body[0]  # type: ignore
@@ -882,6 +882,16 @@ def _build_return_sig(
     return dds_hash_commut(all_pairs)
 
 
+def read_source(f: Callable[..., Any]) -> str:
+    # For functions defined in test modules, the source code is directly
+    # attached to the function.
+    if "__dds_source" in dir(f):
+        src: str = f.__dds_source  # type: ignore
+        return src
+    else:
+        return inspect.getsource(f)
+
+
 _accepted_packages: Set[Package] = {
     Package("dds"),
     Package("__main__"),

From a4028e8c8d3e73c5232a470d63b5ccc7e094934f Mon Sep 17 00:00:00 2001
From: Tim Hunter <tjhunter@cs.stanford.edu>
Date: Sun, 7 Mar 2021 14:46:35 +0100
Subject: [PATCH 2/2] tests that show issue

---
 dds_tests/test_block_boundary.py | 128 +++++++++++++++++++++++++++++++
 1 file changed, 128 insertions(+)
 create mode 100644 dds_tests/test_block_boundary.py

diff --git a/dds_tests/test_block_boundary.py b/dds_tests/test_block_boundary.py
new file mode 100644
index 0000000..7c84152
--- /dev/null
+++ b/dds_tests/test_block_boundary.py
@@ -0,0 +1,128 @@
+import dds
+import pytest
+from .utils import cleandir, Counter
+
+_ = cleandir
+
+_var_function = {}
+
+
+def _dummy():
+    pass
+
+
+def _eval_function(s, function_name, dct):
+    global _var_function
+    _var_function["key"] = None
+    s2 = (
+        s
+        + f"""
+
+global _var_function
+_var_function["key"] = {function_name}
+    """
+    )
+    d = {"_var_function": _var_function, "dds": dds}
+    d.update(dct)
+    exec(s2, d)
+
+    f = _var_function["key"]
+    f.__dds_source = s
+    f.__module__ = _dummy.__module__
+    globals()[function_name] = f
+    return f
+
+
+_c = Counter()
+
+
+def f(i):
+    _ = i
+    _c.increment()
+    return 1
+
+
+subsequent_change_s1 = """
+def function():
+    i = 1
+    _ = dds.keep("/p", f, i)
+    # a
+"""
+
+subsequent_change_s2 = """
+def function():
+    i = 1
+    _ = dds.keep("/p", f, i)
+    # b
+"""
+
+
+@pytest.mark.usefixtures("cleandir")
+def test_subsequent_change():
+    fun = _eval_function(subsequent_change_s1, "function", {"f": f})
+    dds.eval(fun)
+    assert _c.value == 1
+    fun = _eval_function(subsequent_change_s2, "function", {"f": f})
+    dds.eval(fun)
+    assert _c.value == 2
+
+
+next_line_change_s1 = """
+def function():
+    i = 1
+    _ = dds.keep("/p", f, i)
+    
+    # a
+"""
+
+next_line_change_s2 = """
+def function():
+    i = 1
+    _ = dds.keep("/p", f, i)
+    
+    # b
+"""
+
+
+@pytest.mark.usefixtures("cleandir")
+def test_next_line_change():
+    _c.value = 0
+    fun = _eval_function(next_line_change_s1, "function", {"f": f})
+    dds.eval(fun)
+    assert _c.value == 1
+    fun = _eval_function(next_line_change_s2, "function", {"f": f})
+    dds.eval(fun)
+    assert _c.value == 1
+
+
+subexpression_s1 = """
+def function():
+    i = 1
+    _ = [
+      dds.keep("/p", f, i)
+      for x in range(3)
+      if x < 10
+    ]
+"""
+
+subexpression_s2 = """
+def function():
+    i = 1
+    _ = [
+      dds.keep("/p", f, i)
+      for x in range(3)
+      if x < 3  # change
+    ]
+"""
+
+
+@pytest.mark.usefixtures("cleandir")
+def test_subexpression():
+    _c.value = 0
+    fun = _eval_function(subexpression_s1, "function", {"f": f})
+    dds.eval(fun)
+    assert _c.value == 1
+    fun = _eval_function(subexpression_s2, "function", {"f": f})
+    dds.eval(fun)
+    # TODO: should be 2
+    assert _c.value == 1