templates/ident: improve "Identifier not used" message

"Identifier not used" is weird, replace it by "unknown identifier" and
 give the search identifier name in the header.

Also improve the autocomplete comment. Make it human-friendly and
explain why people got autocompleted to a symbol that does not exist.
Also, only show it if the symbol actually exists. That way we only
tell "maybe autocomplete lead you here" only in cases where
autocomplete can actually lead you here.

To test this feature:
 - search for any random symbol, you'll see "Unknown identifier '...'"
 - search for a symbol that exists in another version as the selected
   one. For example __NR_epoll_pwait2 appeared in musl v1.2.5. You'll
   see the same header message plus a comment about how the symbol
   exists in another version.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>

elixir/api.py

@@ -46,7 +46,7 @@ class ApiIdentGetterResource:
         if version == 'latest':
             version = query.get_latest_tag()
 
-        symbol_definitions, symbol_references, symbol_doccomments = query.search_ident(version, ident, family)
+        symbol_definitions, symbol_references, symbol_doccomments, _ = query.search_ident(version, ident, family)
 
         resp.status = falcon.HTTP_200
         resp.content_type = falcon.MEDIA_JSON

elixir/query.py

@@ -212,7 +212,7 @@ class Query:
         ident = parse.quote(ident)
 
         if not self.dts_comp_support or not self.db.comps.exists(ident):
-            return symbol_c, symbol_dts, symbol_docs
+            return symbol_c, symbol_dts, symbol_docs, False
 
         files_this_version = self.db.vers.get(version).iter()
         comps = self.db.comps.get(ident).iter(dummy=True)
@@ -253,7 +253,7 @@ class Query:
         for path, blines in sorted(compsBBuf):
             symbol_docs.append(SymbolInstance(path, blines))
 
-        return symbol_c, symbol_dts, symbol_docs
+        return symbol_c, symbol_dts, symbol_docs, True
 
     def get_idents_defs(self, version, ident, family):
 
@@ -262,10 +262,10 @@ class Query:
         symbol_doccomments = []
 
         if not self.db.defs.exists(ident):
-            return symbol_definitions, symbol_references, symbol_doccomments
+            return symbol_definitions, symbol_references, symbol_doccomments, False
 
         if not self.db.vers.exists(version):
-            return symbol_definitions, symbol_references, symbol_doccomments
+            return symbol_definitions, symbol_references, symbol_doccomments, True
 
         files_this_version = self.db.vers.get(version).iter()
         this_ident = self.db.defs.get(ident)
@@ -330,5 +330,5 @@ class Query:
         for path, docline in sorted(docBuf):
             symbol_doccomments.append(SymbolInstance(path, docline))
 
-        return symbol_definitions, symbol_references, symbol_doccomments
+        return symbol_definitions, symbol_references, symbol_doccomments, True
 

elixir/web.py

@@ -695,7 +695,8 @@ def generate_ident_page(ctx: RequestContext, q: Query,
 
     status = falcon.HTTP_OK
     source_base_url = get_source_base_url(project, version)
-    symbol_definitions, symbol_references, symbol_doccomments = q.search_ident(version, ident, family)
+    symbol_definitions, symbol_references, symbol_doccomments, symbol_exists = q.search_ident(
+            version, ident, family)
     symbol_sections = []
 
     if len(symbol_definitions) or len(symbol_references):
@@ -734,9 +735,8 @@ def generate_ident_page(ctx: RequestContext, q: Query,
                 'message': 'No references found in the database',
             })
 
-    else:
-        if ident != '':
-            status = falcon.HTTP_NOT_FOUND
+    elif ident != '':
+        status = falcon.HTTP_NOT_FOUND
 
     get_url_with_new_version = lambda v: stringify_ident_path(project, v, family, ident)
 
@@ -747,6 +747,8 @@ def generate_ident_page(ctx: RequestContext, q: Query,
         'current_family': family,
 
         'symbol_sections': symbol_sections,
+
+        'symbol_exists': symbol_exists,
     }
 
     template = ctx.jinja_env.get_template('ident.html')

templates/ident.html

@@ -57,8 +57,13 @@
         {% endif %}
     {% endfor %}
 {% else %}
-    <h2>Identifier not used</h2>
-    <div id="error-details">Note: Autocomplete currently searches identifiers in all versions of the project.</div>
+    <h2>Unknown identifier '{{ searched_ident|e }}'</h2>
+    {% if symbol_exists %}
+    <div id="error-details">
+        The '{{ searched_ident|e }}' symbol is defined in another version.
+        Elixir cannot efficiently tell where.
+    </div>
+    {% endif %}
 {% endif %}
 </div>
 

utils/query.py

@@ -16,7 +16,7 @@ def cmd_versions(q, **kwargs):
                 print(v)
 
 def cmd_ident(q, version, ident, family, **kwargs):
-    symbol_definitions, symbol_references, symbol_doccomments = q.search_ident(version, ident, family)
+    symbol_definitions, symbol_references, symbol_doccomments, _ = q.search_ident(version, ident, family)
     print("Symbol Definitions:")
     for symbol_definition in symbol_definitions:
         print(symbol_definition)