(#92): In the use element, honor the overflow:hidden property of a referenced symbol

We meant to look at the referenced <symbol>'s computed values, not the
<use>'s computed values.

Fixes https://gitlab.gnome.org/GNOME/librsvg/-/issues/92

Part-of: <https://gitlab.gnome.org/GNOME/librsvg/-/merge_requests/737>

4 files changed, 28 insertions, 5 deletions

diff --git a/src/drawing_ctx.rs b/src/drawing_ctx.rs
index 6347304f..7ba1c015 100644
--- a/src/drawing_ctx.rs
+++ b/src/drawing_ctx.rs
@@ -108,6 +108,8 @@ pub struct FontOptions {
 #[derive(Debug, Copy, Clone, PartialEq)]
 pub enum ClipMode {
     ClipToViewport,
+
+    // FIXME: this is not used anymore!?
     ClipToVbox,
 }
 
@@ -1690,12 +1692,10 @@ impl DrawingCtx {
             let elt = child.borrow_element();
 
             let symbol = borrow_element_as!(child, Symbol);
+            let symbol_values = elt.get_computed_values();
 
-            let clip_mode = if !values.is_overflow()
-                || (values.overflow() == Overflow::Visible
-                    && elt.get_specified_values().is_overflow())
-            {
-                Some(ClipMode::ClipToVbox)
+            let clip_mode = if !symbol_values.is_overflow() {
+                Some(ClipMode::ClipToViewport)
             } else {
                 None
             };
diff --git a/tests/fixtures/reftests/bugs-reftests/92-symbol-clip-ref.svg b/tests/fixtures/reftests/bugs-reftests/92-symbol-clip-ref.svg
new file mode 100644
index 00000000..c319e2fa
--- /dev/null
+++ b/tests/fixtures/reftests/bugs-reftests/92-symbol-clip-ref.svg
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
+     width="100" height="100" viewBox="0 0 100 100">
+  <rect x="0" y="0" width="40" height="40" fill="lime"/>
+</svg>
diff --git a/tests/fixtures/reftests/bugs-reftests/92-symbol-clip.svg b/tests/fixtures/reftests/bugs-reftests/92-symbol-clip.svg
new file mode 100644
index 00000000..f25b65b2
--- /dev/null
+++ b/tests/fixtures/reftests/bugs-reftests/92-symbol-clip.svg
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
+     width="100" height="100" viewBox="0 0 100 100">
+  <defs>
+    <symbol id="foo" viewBox="0 0 50 50">
+      <rect x="0" y="0" width="40" height="40" fill="lime"/>
+      <rect x="50" y="0" width="40" height="40" fill="red"/>
+    </symbol>
+  </defs>
+
+  <use x="0" y="0" width="50" height="50" xlink:href="#foo"/>
+</svg>
diff --git a/tests/src/reference.rs b/tests/src/reference.rs
index 665baec0..00d6428c 100644
--- a/tests/src/reference.rs
+++ b/tests/src/reference.rs
@@ -406,3 +406,9 @@ test_svg_reference!(
     "tests/fixtures/reftests/bugs-reftests/880-stroke-wide-line.svg",
     "tests/fixtures/reftests/bugs-reftests/880-stroke-wide-line-ref.svg"
 );
+
+test_svg_reference!(
+    bug_92_symbol_clip,
+    "tests/fixtures/reftests/bugs-reftests/92-symbol-clip.svg",
+    "tests/fixtures/reftests/bugs-reftests/92-symbol-clip-ref.svg"
+);