Merge pull request #328 from linebender/accept-always-on-rules

Accept empty condition sets
linebender · Oct 12, 2023 · 8a69746 · 8a69746
2 parents 9d87c2b + 5dbaffb
commit 8a69746
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Showing 4 changed files with 65 additions and 3 deletions.
diff --git a/src/designspace.rs b/src/designspace.rs
@@ -120,7 +120,8 @@ pub struct Rule {
     /// Name of the rule.
     #[serde(rename = "@name")]
     pub name: Option<String>,
-    /// Condition sets. If any condition is true, the rule is applied.
+    /// Condition sets. If any condition is true or the condition set is empty,
+    /// the rule is applied.
     #[serde(rename = "conditionset")]
     pub condition_sets: Vec<ConditionSet>,
     /// Subtitutions (in, out).
@@ -143,7 +144,7 @@ pub struct Substitution {
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)]
 pub struct ConditionSet {
     /// The conditions.
-    #[serde(rename = "condition")]
+    #[serde(rename = "condition", default)]
     pub conditions: Vec<Condition>,
 }
 
@@ -541,4 +542,37 @@ mod tests {
         );
         assert_eq!(ds_initial, ds_after);
     }
+
+    #[test]
+    fn accept_always_on_rules() {
+        // Given
+        let designspace =
+            DesignSpaceDocument::load("testdata/MutatorSansAlwaysOnRules.designspace").unwrap();
+
+        // Then
+        assert_eq!(
+            &designspace.rules,
+            &Rules {
+                processing: RuleProcessing::Last,
+                rules: vec![
+                    Rule {
+                        name: Some("fold_I_serifs".into()),
+                        condition_sets: vec![ConditionSet { conditions: vec![] }],
+                        substitutions: vec![Substitution {
+                            name: "I".into(),
+                            with: "I.narrow".into()
+                        }],
+                    },
+                    Rule {
+                        name: Some("fold_S_terminals".into()),
+                        condition_sets: vec![ConditionSet { conditions: vec![] }],
+                        substitutions: vec![Substitution {
+                            name: "S".into(),
+                            with: "S.closed".into()
+                        }],
+                    },
+                ]
+            }
+        );
+    }
 }
diff --git a/src/error.rs b/src/error.rs
@@ -524,7 +524,7 @@ pub enum ErrorKind {
     BadImage,
     /// Has an invalid identifier.
     BadIdentifier,
-    /// Name is not a valid [`Name`](crate::Name).
+    /// Name is not a valid [`Name`].
     InvalidName,
     /// Has an invalid lib.
     BadLib,

diff --git a/src/glyph/mod.rs b/src/glyph/mod.rs
@@ -342,6 +342,7 @@ impl Contour {
                 .map(|idx| self.points.len() - 1 - idx);
             self.points.iter().cycle().skip(rotate.unwrap_or(0)).take(self.points.len() + 1)
         } else {
+            #[allow(clippy::iter_skip_zero)]
             self.points.iter().cycle().skip(0).take(self.points.len())
         };
         if let Some(start) = points.next() {

diff --git a/testdata/MutatorSansAlwaysOnRules.designspace b/testdata/MutatorSansAlwaysOnRules.designspace
@@ -0,0 +1,27 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<designspace format="4.1">
+  <axes>
+    <axis tag="wdth" name="width" minimum="0" maximum="1000" default="0"/>
+    <axis tag="wght" name="weight" minimum="0" maximum="1000" default="0"/>
+  </axes>
+  <rules processing="last">
+    <rule name="fold_I_serifs">
+      <conditionset>
+      </conditionset>
+      <sub name="I" with="I.narrow"/>
+    </rule>
+    <rule name="fold_S_terminals">
+      <conditionset>
+      </conditionset>
+      <sub name="S" with="S.closed"/>
+    </rule>
+  </rules>
+  <sources>
+    <source filename="MutatorSansLightCondensed.ufo" familyname="MutatorMathTest" stylename="LightCondensed">
+      <location>
+        <dimension name="width" xvalue="0"/>
+        <dimension name="weight" xvalue="0"/>
+      </location>
+    </source>
+  </sources>
+</designspace>