fix: issue where -0 lost its sign

Author: yisibl

src/lib.rs

@@ -7795,6 +7795,10 @@ mod tests {
       ".infinity11-6 { z-index: calc(2147483647 + 2 - 1) }",
       ".infinity11-6{z-index:calc(1/0)}", // 2147483647
     );
+    minify_test(
+      ".infinity11-7 { z-index: calc(1 - 2147483649) }",
+      ".infinity11-7{z-index:calc(-1/0)}", // Negative overflow: 1 + (-2147483649) = -2147483648
+    );
     minify_test(
       ".infinity12-1 { z-index: calc(calc(1/0) + infinity) }",
       ".infinity12-1{z-index:calc(1/0)}",
@@ -7821,8 +7825,64 @@ mod tests {
       ".infinity6{order:calc(1/0)}",
     );
     minify_test(
-      ".infinity-flex { flex: calc(6 / 0); }",
-      ".infinity-flex{flex:calc(1/0)}",
+      ".infinity-new2 { transition-timing-function: steps(calc(infinity), jump-start) }",
+      ".infinity-new2{transition-timing-function:steps(calc(1/0),start)}",
+    );
+    minify_test(
+      ".infinity-new3 { transition: steps(calc(infinity), jump-start) }",
+      ".infinity-new3{transition:all steps(calc(1/0),start)}",
+    );
+
+    // Test Infinity <length> - division by zero should preserve sign
+    minify_test(
+      ".infinity-dim1 { width: calc(100px / 0) }",
+      ".infinity-dim1{width:calc(100px/0)}",
+    );
+    minify_test(
+      ".infinity-dim2 { width: calc(100px / -0) }",
+      ".infinity-dim2{width:calc(100px/-0)}",
+    );
+    minify_test(
+      ".infinity-dim3 { width: calc(-100px / 0) }",
+      ".infinity-dim3{width:calc(-100px/0)}",
+    );
+    minify_test(
+      ".infinity-dim4 { width: calc(-100px / -0) }",
+      ".infinity-dim4{width:calc(-100px/-0)}",
+    );
+    minify_test(
+      ".infinity-dim5 { width: calc(-0px); height: calc(-0); }",
+      ".infinity-dim5{width:0;height:0}",
+    );
+
+    // Test Infinity <number>
+    minify_test(
+      ".number1 { line-height: calc(9/0) }",
+      ".number1{line-height:calc(1/0)}",
+    );
+    minify_test(
+      ".number2 { line-height: calc(0.0002/0) }",
+      ".number2{line-height:calc(1/0)}",
+    );
+    minify_test(
+      ".number3 { line-height: calc(-1/0) }",
+      ".number3{line-height:calc(-1/0)}",
+    );
+    minify_test(
+      ".number3-1 { line-height: calc(1/-0) }",
+      ".number3-1{line-height:calc(-1/0)}",
+    );
+    minify_test(
+      ".number3-1 { flex: calc(0/-0) }",
+      ".number3-1{flex:0}",
+    );
+    minify_test(
+      ".number4 { flex: calc(1 * infinity) }",
+      ".number4{flex:calc(1/0)}",
+    );
+    minify_test(
+      ".number5 { flex: calc(-1 * infinity) }",
+      ".number5{flex:calc(-1/0)}",
     );
 
     // TODO Support orphans prop

src/properties/position.rs

@@ -91,7 +91,10 @@ pub enum ZIndex {
 
 impl<'i> Parse<'i> for ZIndex {
   fn parse<'t>(input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i, ParserError<'i>>> {
-    if input.try_parse(|input| input.expect_ident_cloned()).is_ok() {
+    if input
+      .try_parse(|input| input.expect_ident_matching("auto"))
+      .is_ok()
+    {
       return Ok(ZIndex::Auto);
     }
 

src/rules/font_palette_values.rs

@@ -187,7 +187,7 @@ impl<'i> Parse<'i> for BasePalette {
       if i.is_negative() {
         return Err(input.new_custom_error(ParserError::InvalidValue));
       }
-      return Ok(BasePalette::Integer(i32::from(i) as u16));
+      return Ok(BasePalette::Integer(*i as u16));
     }
 
     let location = input.current_source_location();
@@ -226,7 +226,7 @@ impl<'i> Parse<'i> for OverrideColors {
     }
 
     Ok(OverrideColors {
-      index: i32::from(index) as u16,
+      index: (*index) as u16,
       color,
     })
   }
@@ -237,7 +237,7 @@ impl ToCss for OverrideColors {
   where
     W: std::fmt::Write,
   {
-    CSSInteger(i32::from(self.index)).to_css(dest)?;
+    CSSInteger(self.index as i32).to_css(dest)?;
     dest.write_char(' ')?;
     self.color.to_css(dest)
   }

src/values/calc.rs

@@ -629,7 +629,10 @@ impl<
               }
               // Non-Number (like Length) / 0 = infinity
               // For Length values, we keep them as-is and let ToCss handle serialization
-              node = Calc::Product(1.0, Box::new(node));
+              // Use f32::INFINITY as marker for division by zero
+              // In ToCss, we'll output /0 or /-0 based on the marker
+              let marker = if f32::is_sign_negative(val) { -f32::INFINITY } else { f32::INFINITY };
+              node = Calc::Product(marker, Box::new(node));
               continue;
             }
             // Division by infinity
@@ -1010,9 +1013,18 @@ impl<V: ToCss + std::ops::Mul<f32, Output = V> + TrySign + Clone + std::fmt::Deb
         }
       }
       Calc::Product(num, calc) => {
-        // Special case: Product(1, value) represents value/0 (infinity)
-        // Serialize as calc(value/0) instead of calc(1 * value)
-        if *num == 1.0 {
+        // Special case: Product(INFINITY, value) represents value/0 (division by positive zero)
+        // Special case: Product(-INFINITY, value) represents value/-0 (division by negative zero)
+        // Serialize as calc(value/0) or calc(value/-0) instead of calc(INFINITY * value)
+        if num.is_infinite() {
+          calc.to_css(dest)?;
+          dest.delim('/', true)?;
+          if f32::is_sign_negative(*num) {
+            dest.write_str("-0")
+          } else {
+            dest.write_str("0")
+          }
+        } else if *num == 1.0 {
           calc.to_css(dest)?;
           dest.delim('/', true)?;
           dest.write_str("0")

src/values/number.rs

@@ -265,8 +265,10 @@ impl AddInternal for CSSInteger {
   fn add(self, other: Self) -> Self {
     let result = self.0.saturating_add(other.0);
     // Check for overflow and produce infinity
-    if result == i32::MAX || result == i32::MIN {
+    if result == i32::MAX {
       CSSInteger(i32::MAX)
+    } else if result == i32::MIN {
+      CSSInteger(i32::MIN)
     } else {
       CSSInteger(result)
     }