# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1479164421 -3600
# Node ID c4236e61a4f682f423e480e860768e72faf83eca
# Parent  b7860ad65334408782d9e9023227095fd0073ecc
Attempt to provide usable references for inter-module dependencies, identifying
them completely when object identity information is needed, exposing module
provider information otherwise.
Removed tests for "<depends>" references in cached output since inter-module
dependencies will appear as such in the name references section of each file.

diff -r b7860ad65334 -r c4236e61a4f6 importer.py
--- a/importer.py	Sun Nov 13 22:18:29 2016 +0100
+++ b/importer.py	Tue Nov 15 00:00:21 2016 +0100
@@ -187,6 +187,15 @@
 
         "Identify 'name' using stored object and external name records."
 
+        ref = self.follow(name)
+        if ref and ref.has_kind("<depends>"):
+            ref = self.follow(ref.get_origin())
+        return ref
+
+    def follow(self, name):
+
+        "Identify 'name' using stored object and external name records."
+
         ref = self.objects.get(name)
         if not ref or ref.has_kind("<module>"):
             ref = self.all_name_references.get(name) or ref
@@ -248,10 +257,7 @@
 
         "Return from 'object_type' the details of module attribute 'attrname'."
 
-        if attrname in self.all_module_attrs[object_type]:
-            return self.get_object("%s.%s" % (object_type, attrname))
-        else:
-            return None
+        return self.identify("%s.%s" % (object_type, attrname))
 
     # Convenience methods for deducing which kind of object provided an
     # attribute.
@@ -406,8 +412,8 @@
             # Resolve all deferred references in each module.
 
             for ref in module.deferred:
-                found = self.find_dependency(ref)
-                if not found:
+                dependency = self.find_dependency(ref)
+                if not dependency:
                     self.missing.add((module.name, ref.get_origin()))
 
                 # Record the resolved names and identify required modules.
@@ -416,9 +422,17 @@
                     # Find the providing module of this reference.
                     # Where definitive details of the origin cannot be found,
                     # identify the provider using the deferred reference.
-                    # NOTE: This may need to test for static origins.
+
+                    provider = self.get_module_provider(dependency.unresolved() and ref or dependency)
+
+                    # Only mutate references to the eventual object if it is
+                    # static. Otherwise, maintain the closest referrer.
 
-                    provider = self.get_module_provider(found.unresolved() and ref or found)
+                    if dependency.static():
+                        found = dependency
+                    else:
+                        found = self.find_reference(ref)
+
                     ref.mutate(found)
 
                     if provider:
@@ -468,7 +482,22 @@
         found = set()
         while ref and ref.has_kind("<depends>") and not ref in found:
             found.add(ref)
-            ref = self.identify(ref.get_origin())
+            ref = self.follow(ref.get_origin())
+        return ref
+
+    def find_reference(self, ref):
+
+        "Find the ultimate usable reference for 'ref'."
+
+        found = set()
+        while ref:
+            found.add(ref)
+            next_ref = self.follow(ref.get_origin())
+            if not next_ref or next_ref in found:
+                return ref
+            if not next_ref.has_kind("<depends>") and not next_ref.static():
+                return ref
+            ref = next_ref
         return ref
 
     def get_module_provider(self, ref):
diff -r b7860ad65334 -r c4236e61a4f6 test_all.sh
--- a/test_all.sh	Sun Nov 13 22:18:29 2016 +0100
+++ b/test_all.sh	Tue Nov 15 00:00:21 2016 +0100
@@ -41,16 +41,6 @@
     echo "$FILENAME..." 1>&2
     if ! ./lplc "$FILENAME" -r ; then exit 1 ; fi
 
-    # Check for unresolved names in the cache.
-
-    echo " (depends)..." 1>&2
-    if grep '<depends>' -r "_cache" && \
-       ! expect_failure ; then
-
-       echo "Unresolved names in the cache." 1>&2
-       exit 1
-    fi
-
     # Check for type warnings in deduction output.
 
     echo " (warnings)..." 1>&2