fix module-path-index spec and use related to resolved module paths

svn: r11523

collects/scribblings/reference/module-reflect.scrbl

@@ -154,20 +154,21 @@ the form of a @deftech{module path index}. A @tech{module path index}
 is a semi-interned (multiple references to the same relative module
 tend to use the same @tech{module path index} value, but not always)
 opaque value that encodes a module path (see @scheme[module-path?])
-and another @tech{module path index} to which it is relative.
+and either a @tech{resolved module path} or another @tech{module path
+index} to which it is relative.
 
 A @tech{module path index} that uses both @scheme[#f] for its path and
 base @tech{module path index} represents ``self''---i.e., the module
 declaration that was the source of the @tech{module path index}---and
-such a @tech{module path index} is always used as the root for a chain
-of @tech{module path index}. For example, when extracting information
-about an identifier's binding within a module, if the identifier is
-bound by a definition within the same module, the identifier's source
-module is reported using the ``self'' @tech{module path index}. If the
-identifier is instead defined in a module that is imported via a
-module path (as opposed to a literal module name), then the
-identifier's source module will be reported using a @tech{module path
-index} that contains the @scheme[require]d module path and the
+such a @tech{module path index} can be used as the root for a chain of
+@tech{module path index}es at compile time. For example, when
+extracting information about an identifier's binding within a module,
+if the identifier is bound by a definition within the same module, the
+identifier's source module is reported using the ``self'' @tech{module
+path index}. If the identifier is instead defined in a module that is
+imported via a module path (as opposed to a literal module name), then
+the identifier's source module will be reported using a @tech{module
+path index} that contains the @scheme[require]d module path and the
 ``self'' @tech{module path index}.
 
 
@@ -204,7 +205,7 @@ resolved name can depend on the value of
 
 @defproc[(module-path-index-split [mpi module-path-index?])
          (values (or/c module-path? false/c)
-                 (or/c module-path-index? false/c))]{
+                 (or/c module-path-index? resolved-module-path? false/c))]{
 
 Returns two values: a module path, and a base @tech{module path index}
 or @scheme[#f] to which the module path is relative.
@@ -219,7 +220,7 @@ second result, and means that @scheme[mpi] represents ``self'' (see
 above).}
 
 @defproc[(module-path-index-join [path (or/c module-path? false/c)]
-                                 [mpi (or/c module-path-index? false/c)])
+                                 [mpi (or/c module-path-index? resolved-module-path? false/c)])
          module-path-index?]{
 
 Combines @scheme[path] and @scheme[mpi] to create a new @tech{module

collects/syntax/private/modcollapse-noctc.ss

@@ -263,9 +263,15 @@ Use syntax/modcollapse instead.
     (if path
         (collapse-module-path
          path
-         (if base
-             (collapse-module-path-index base relto-mp)
-             relto-mp))
+         (cond
+          [(module-path-index? base)
+           (collapse-module-path-index base relto-mp)]
+          [(resolved-module-path? base)
+           (let ([n (resolved-module-path-name base)])
+             (if (path? n)
+                 n
+                 relto-mp))]
+          [else relto-mp]))
         relto-mp)))
 
 (provide collapse-module-path

collects/tests/mzscheme/moddep.ss

@@ -128,6 +128,16 @@
 
 (test-cmp (build-path 'same "x.ss") "x.ss" (build-path 'same))
 
+(test '(lib "bar/foo.ss")
+      collapse-module-path-index 
+      (module-path-index-join '(lib "foo.ss" "bar") (make-resolved-module-path 'nowhere))
+      (current-directory))
+(test (build-path (find-system-path 'temp-dir) "data.ss")
+      collapse-module-path-index 
+      (module-path-index-join '"data.ss" (make-resolved-module-path
+                                          (build-path (find-system-path 'temp-dir) "prog.ss")))
+      (current-directory))
+
 ;; Try path cases that don't fit UTF-8 (and therefore would go wrong as a string):
 (let ([dir (build-path (current-directory) (bytes->path #"\xFF"))])
   (test-cmp (build-path dir "x.ss")