uri: fix empty query/fragment offsets

test/uri.cpp

@@ -376,6 +376,45 @@ test_validity (cruft::TAP::logger &tap)
 }
 
 
+///////////////////////////////////////////////////////////////////////////////
+static void
+test_pqf (cruft::TAP::logger &tap)
+{
+    static constexpr struct {
+        char const *uri;
+        char const *pq;
+        char const *pqf;
+    } TESTS[] = {
+        {
+            "http://example.com/foo?bar#qux",
+            "/foo?bar",
+            "/foo?bar#qux"
+        },
+        {
+            "http://example.com/foo",
+            "/foo",
+            "/foo",
+        },
+        {
+            "http://example.com/foo?#qux",
+            "/foo?",
+            "/foo?#qux"
+        },
+        {
+            "http://example.com/foo?bar#",
+            "/foo?bar",
+            "/foo?bar#"
+        }
+    };
+
+    for (auto const &t: TESTS) {
+        cruft::uri const obj (t.uri);
+        tap.expect_eq (t.pq,  obj.pq  (), "pq: {}", t.uri);
+        tap.expect_eq (t.pqf, obj.pqf (), "pqf: {}", t.uri);
+    }
+}
+
+
 ///////////////////////////////////////////////////////////////////////////////
 int
 main (void)
@@ -387,6 +426,7 @@ main (void)
     test_normalise (tap);
     test_rfc_resolve (tap);
     test_resolve (tap);
+    test_pqf (tap);
 
     return tap.status ();
 }

uri.cpp

@@ -31,9 +31,20 @@ cruft::uri::uri (std::string &&_value):
 
     parse ();
 
+    // Ensure the offsets are well-ordered.
+    //
+    // We want the QUERY offsets to come after the PATH offsets even if there
+    // is no QUERY data (or at least be placed coincident with the PATH
+    // offsets).
     for (int i = 1; i < NUM_COMPONENTS; ++i) {
-        if (m_offsets[i].second != m_offsets[i].first)
+        // We very specifically do not want to move any offset that has a
+        // non-zero (ie, found) offset.
+        //
+        // If we do, this prevents us from computing `pqf` and retaining a
+        // trailing "?" for an empty query.
+        if (m_offsets[i].second or m_offsets[i].first)
             continue;
+
         m_offsets[i] = {
             m_offsets[i - 1].second,
             m_offsets[i - 1].second

uri.hpp

@@ -99,7 +99,9 @@ namespace cruft {
         std::string_view heirarchical (void) const&; //{ return { user ().begin (), path ().end () }; }
         std::string_view authority (void) const&; //{ return { user ().begin (), port ().end () }; }
 
-        std::string_view pq (void) const&
+        /// Returns a view over the path and query components
+        std::string_view
+        pq (void) const&
         {
             return {
                 m_value.data () + m_offsets[PATH].first,
@@ -107,6 +109,7 @@ namespace cruft {
             };
         }
 
+        /// Returns a view over the path, query, and fragment components
         std::string_view
         pqf (void) const& {
             return {