chore: simplify conditional attributes

Author: hperrin

packages/common/Label.svelte

@@ -10,7 +10,7 @@
     {context === 'image-list' ? 'mdc-image-list__label' : ''}
     {context === 'snackbar' ? 'mdc-snackbar__label' : ''}
   "
-  {...snackbarProps}
+  {...((context === 'snackbar') ? {role: 'status', 'aria-live': 'polite'} : {})}
   {...exclude($$props, ['use', 'class'])}
 ><slot></slot></span>
 
@@ -28,6 +28,4 @@
   export {className as class};
 
   const context = getContext('SMUI:label:context');
-
-  $: snackbarProps = (context === 'snackbar') ? {role: 'status', 'aria-live': 'polite'} : {};
 </script>

packages/data-table/Row.svelte

@@ -8,7 +8,7 @@
     {!header ? 'mdc-data-table__row' : ''}
     {(!header && selected) ? 'mdc-data-table__row--selected' : ''}
   "
-  {...ariaSelectedProp}
+  {...(selected !== undefined ? {'aria-selected': selected ? 'true' : 'false'} : {})}
   {...exclude($$props, ['use', 'class'])}
 ><slot></slot></tr>
 
@@ -29,8 +29,6 @@
   let header = getContext('SMUI:data-table:row:header');
   let selected = undefined;
 
-  $: ariaSelectedProp = selected !== undefined ? {'aria-selected': selected ? 'true' : 'false'} : {};
-
   setContext('SMUI:data-table:row:getIndex', getIndex);
 
   setContext('SMUI:generic:input:setChecked', setChecked);

packages/floating-label/FloatingLabel.svelte

@@ -12,7 +12,7 @@
     use:useActions={use}
     use:forwardEvents
     class="mdc-floating-label {className}"
-    {...forProp}
+    {...((forId || inputProps && inputProps.id) ? {'for': forId || inputProps && inputProps.id} : {})}
     {...exclude($$props, ['use', 'class', 'for', 'wrapped'])}
   ><slot></slot></label>
 {/if}
@@ -38,8 +38,6 @@
   let floatingLabel;
   let inputProps = getContext('SMUI:generic:input:props') || {};
 
-  $: forProp = (forId || inputProps && inputProps.id) ? {for: forId || inputProps && inputProps.id} : {};
-
   onMount(() => {
     floatingLabel = new MDCFloatingLabel(element);
   });

packages/list/Label.svelte

@@ -2,7 +2,7 @@
   use:useActions={use}
   use:forwardEvents
   class="mdc-list-item__text {className}"
-  {...forProp}
+  {...((inputProps && inputProps.id) ? {'for': inputProps && inputProps.id} : {})}
   {...exclude($$props, ['use', 'class'])}
 ><slot></slot></label>
 
@@ -20,6 +20,4 @@
   export {className as class};
 
   let inputProps = getContext('SMUI:generic:input:props') || {};
-
-  $: forProp = (inputProps && inputProps.id) ? {for: inputProps && inputProps.id} : {};
 </script>

packages/menu/SelectionGroup.svelte

@@ -20,8 +20,6 @@
   const forwardEvents = forwardEventsBuilder(current_component);
 
   export let use = [];
-  let className = '';
-  export {className as class};
   export let list$use = [];
   export let list$class = '';
 </script>

packages/textfield/Textfield.svelte

@@ -42,7 +42,7 @@
         {updateInvalid}
         on:change
         on:input
-        {...placeholderProp}
+        {...((fullwidth && label) ? {placeholder: label} : {})}
         {...prefixFilter($$props, 'input$')}
       />
     {/if}
@@ -134,8 +134,6 @@
 
   $: valued = value !== uninitializedValue || files !== uninitializedValue;
 
-  $: placeholderProp = (fullwidth && label) ? {placeholder: label} : {};
-
   $: if (textField && value !== uninitializedValue && textField.value !== value) {
     textField.value = value;
   }

packages/top-app-bar/Section.svelte

@@ -7,7 +7,7 @@
     {align === 'start' ? 'mdc-top-app-bar__section--align-start' : ''}
     {align === 'end' ? 'mdc-top-app-bar__section--align-end' : ''}
   "
-  {...roleProp}
+  {...(toolbar ? {role: 'toolbar'} : {})}
   {...exclude($$props, ['use', 'class', 'align', 'toolbar'])}
 ><slot></slot></section>
 
@@ -26,8 +26,6 @@
   export let align = 'start';
   export let toolbar = false;
 
-  $: roleProp = toolbar ? {role: 'toolbar'} : {};
-
   setContext('SMUI:icon-button:context', toolbar ? 'top-app-bar:action' : 'top-app-bar:navigation');
   setContext('SMUI:button:context', toolbar ? 'top-app-bar:action' : 'top-app-bar:navigation');
 </script>