Auto merge of #18498 - upsuper:enum-keyword-exhaustive, r=emilio

Use exhaustive match for cloning keyword value by default for property using enum class

rather than casting them to `u8` then do inexhaustive match.

I don't see why we couldn't do this.

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components/style/properties/gecko.mako.rs

@@ -472,6 +472,7 @@ def set_gecko_property(ffi_name, expr):
         // as signed type when we have both signed/unsigned integer in order to use them
         // as match's arms.
         // Also, to use same implementation here we use casted constant if we have only singed values.
+        % if keyword.gecko_enum_prefix is None:
         % for value in keyword.values_for('gecko'):
         const ${keyword.casted_constant_name(value, cast_type)} : ${cast_type} =
             structs::${keyword.gecko_constant(value)} as ${cast_type};
@@ -485,6 +486,16 @@ def set_gecko_property(ffi_name, expr):
             x => panic!("Found unexpected value in style struct for ${ident} property: {:?}", x),
             % endif
         }
+        % else:
+        match ${get_gecko_property(gecko_ffi_name)} {
+            % for value in keyword.values_for('gecko'):
+            structs::${keyword.gecko_constant(value)} => Keyword::${to_rust_ident(value)},
+            % endfor
+            % if keyword.gecko_inexhaustive:
+            x => panic!("Found unexpected value in style struct for ${ident} property: {:?}", x),
+            % endif
+        }
+        % endif
     }
 </%def>
 
@@ -2823,7 +2834,6 @@ fn static_assert() {
                                             "-moz-grid-group -moz-grid-line -moz-stack -moz-inline-stack -moz-deck " +
                                             "-moz-popup -moz-groupbox",
                                             gecko_enum_prefix="StyleDisplay",
-                                            gecko_inexhaustive="True",
                                             gecko_strip_moz_prefix=False) %>
 
     pub fn set_display(&mut self, v: longhands::display::computed_value::T) {

components/style/properties/longhand/border.mako.rs

@@ -195,14 +195,12 @@ ${helpers.gecko_keyword_conversion(Keyword('border-style',
 
 ${helpers.single_keyword("box-decoration-break", "slice clone",
                          gecko_enum_prefix="StyleBoxDecorationBreak",
-                         gecko_inexhaustive=True,
                          spec="https://drafts.csswg.org/css-break/#propdef-box-decoration-break",
                          products="gecko", animation_value_type="discrete")}
 
 ${helpers.single_keyword("-moz-float-edge", "content-box margin-box",
                          gecko_ffi_name="mFloatEdge",
                          gecko_enum_prefix="StyleFloatEdge",
-                         gecko_inexhaustive=True,
                          products="gecko",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-float-edge)",
                          animation_value_type="discrete")}

components/style/properties/longhand/box.mako.rs

@@ -1793,7 +1793,6 @@ ${helpers.single_keyword("-moz-orient",
                           gecko_ffi_name="mOrient",
                           gecko_enum_prefix="StyleOrient",
                           spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-orient)",
-                          gecko_inexhaustive="True",
                           animation_value_type="discrete")}
 
 <%helpers:longhand name="will-change" products="gecko" animation_value_type="discrete"

components/style/properties/longhand/inherited_svg.mako.rs

@@ -45,7 +45,6 @@ ${helpers.predefined_type("fill-opacity", "SVGOpacity", "Default::default()",
 
 ${helpers.single_keyword("fill-rule", "nonzero evenodd",
                          gecko_enum_prefix="StyleFillRule",
-                         gecko_inexhaustive=True,
                          products="gecko", animation_value_type="discrete",
                          spec="https://www.w3.org/TR/SVG11/painting.html#FillRuleProperty")}
 
@@ -110,7 +109,6 @@ ${helpers.predefined_type(
 ${helpers.single_keyword("clip-rule", "nonzero evenodd",
                          products="gecko",
                          gecko_enum_prefix="StyleFillRule",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          spec="https://www.w3.org/TR/SVG11/masking.html#ClipRuleProperty")}
 

components/style/properties/longhand/inherited_text.mako.rs

@@ -25,7 +25,6 @@ ${helpers.single_keyword("text-transform",
 
 ${helpers.single_keyword("hyphens", "manual none auto",
                          gecko_enum_prefix="StyleHyphens",
-                         gecko_inexhaustive=True,
                          products="gecko", animation_value_type="discrete", extra_prefixes="moz",
                          spec="https://drafts.csswg.org/css-text/#propdef-hyphens")}
 
@@ -66,7 +65,6 @@ ${helpers.single_keyword("word-break",
                                   extra_gecko_values="inter-character"
                                   extra_specified="${'distribute' if product == 'gecko' else ''}"
                                   gecko_enum_prefix="StyleTextJustify"
-                                  gecko_inexhaustive="True"
                                   animation_value_type="discrete"
                                   flags="APPLIES_TO_PLACEHOLDER",
                                   spec="https://drafts.csswg.org/css-text/#propdef-text-justify">
@@ -368,7 +366,6 @@ ${helpers.predefined_type("word-spacing",
                                   extra_gecko_values="-moz-pre-space"
                                   gecko_enum_prefix="StyleWhiteSpace"
                                   needs_conversion="True"
-                                  gecko_inexhaustive="True"
                                   animation_value_type="discrete"
                                   // Only allowed for UA sheets, which set it
                                   // !important.

components/style/properties/longhand/pointing.mako.rs

@@ -155,7 +155,6 @@ ${helpers.single_keyword("pointer-events", "auto none", animation_value_type="di
 ${helpers.single_keyword("-moz-user-input", "auto none enabled disabled",
                          products="gecko", gecko_ffi_name="mUserInput",
                          gecko_enum_prefix="StyleUserInput",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-user-input)")}
 
@@ -163,7 +162,6 @@ ${helpers.single_keyword("-moz-user-modify", "read-only read-write write-only",
                          products="gecko", gecko_ffi_name="mUserModify",
                          gecko_enum_prefix="StyleUserModify",
                          needs_conversion=True,
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-user-modify)")}
 
@@ -171,7 +169,6 @@ ${helpers.single_keyword("-moz-user-focus",
                          "none ignore normal select-after select-before select-menu select-same select-all",
                          products="gecko", gecko_ffi_name="mUserFocus",
                          gecko_enum_prefix="StyleUserFocus",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-user-focus)")}
 

components/style/properties/longhand/position.mako.rs

@@ -232,7 +232,6 @@ ${helpers.single_keyword("box-sizing",
                          spec="https://drafts.csswg.org/css-ui/#propdef-box-sizing",
                          gecko_enum_prefix="StyleBoxSizing",
                          custom_consts={ "content-box": "Content", "border-box": "Border" },
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete")}
 
 ${helpers.single_keyword("object-fit", "fill contain cover none scale-down",

components/style/properties/longhand/ui.mako.rs

@@ -22,7 +22,6 @@ ${helpers.single_keyword("-moz-user-select", "auto text none all element element
                          alias="-webkit-user-select",
                          gecko_ffi_name="mUserSelect",
                          gecko_enum_prefix="StyleUserSelect",
-                         gecko_inexhaustive=True,
                          gecko_strip_moz_prefix=False,
                          aliases="-moz-none=none",
                          animation_value_type="discrete",
@@ -31,14 +30,12 @@ ${helpers.single_keyword("-moz-user-select", "auto text none all element element
 ${helpers.single_keyword("-moz-window-dragging", "default drag no-drag", products="gecko",
                          gecko_ffi_name="mWindowDragging",
                          gecko_enum_prefix="StyleWindowDragging",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          spec="None (Nonstandard Firefox-only property)")}
 
 ${helpers.single_keyword("-moz-window-shadow", "none default menu tooltip sheet", products="gecko",
                          gecko_ffi_name="mWindowShadow",
                          gecko_constant_prefix="NS_STYLE_WINDOW_SHADOW",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          internal=True,
                          spec="None (Nonstandard internal property)")}

components/style/properties/longhand/xul.mako.rs

@@ -11,7 +11,6 @@
 ${helpers.single_keyword("-moz-box-align", "stretch start center baseline end",
                          products="gecko", gecko_ffi_name="mBoxAlign",
                          gecko_enum_prefix="StyleBoxAlign",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          alias="-webkit-box-align",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/box-align)")}
@@ -19,7 +18,6 @@ ${helpers.single_keyword("-moz-box-align", "stretch start center baseline end",
 ${helpers.single_keyword("-moz-box-direction", "normal reverse",
                          products="gecko", gecko_ffi_name="mBoxDirection",
                          gecko_enum_prefix="StyleBoxDirection",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          alias="-webkit-box-direction",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/box-direction)")}
@@ -34,7 +32,6 @@ ${helpers.single_keyword("-moz-box-orient", "horizontal vertical",
                          products="gecko", gecko_ffi_name="mBoxOrient",
                          extra_gecko_aliases="inline-axis=horizontal block-axis=vertical",
                          gecko_enum_prefix="StyleBoxOrient",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          alias="-webkit-box-orient",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/box-orient)")}
@@ -42,7 +39,6 @@ ${helpers.single_keyword("-moz-box-orient", "horizontal vertical",
 ${helpers.single_keyword("-moz-box-pack", "start center end justify",
                          products="gecko", gecko_ffi_name="mBoxPack",
                          gecko_enum_prefix="StyleBoxPack",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          alias="-webkit-box-pack",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/box-pack)")}
@@ -50,7 +46,6 @@ ${helpers.single_keyword("-moz-box-pack", "start center end justify",
 ${helpers.single_keyword("-moz-stack-sizing", "stretch-to-fit ignore ignore-horizontal ignore-vertical",
                          products="gecko", gecko_ffi_name="mStackSizing",
                          gecko_enum_prefix="StyleStackSizing",
-                         gecko_inexhaustive=True,
                          animation_value_type="discrete",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-stack-sizing)")}