data: flipFilter

3 files changed, 38 insertions, 0 deletions

diff --git a/src/data/composite/control-flow/flipFilter.js b/src/data/composite/control-flow/flipFilter.js
new file mode 100644
index 00000000..995bacad
--- /dev/null
+++ b/src/data/composite/control-flow/flipFilter.js
@@ -0,0 +1,36 @@
+// Flips a filter, so that each true item becomes false, and vice versa.
+// Overwrites the provided dependency.
+//
+// See also:
+//  - withAvailabilityFilter
+
+import {input, templateCompositeFrom} from '#composite';
+
+export default templateCompositeFrom({
+  annotation: `flipFilter`,
+
+  inputs: {
+    filter: input({type: 'array'}),
+  },
+
+  outputs: ({
+    [input.staticDependency('filter')]: filterDependency,
+  }) => [filterDependency ?? '#flippedFilter'],
+
+  steps: () => [
+    {
+      dependencies: [
+        input('filter'),
+        input.staticDependency('filter'),
+      ],
+
+      compute: (continuation, {
+        [input('filter')]: filter,
+        [input.staticDependency('filter')]: filterDependency,
+      }) => continuation({
+        [filterDependency ?? '#flippedFilter']:
+          filter.map(item => !item),
+      }),
+    },
+  ],
+});
diff --git a/src/data/composite/control-flow/index.js b/src/data/composite/control-flow/index.js
index 7e137a14..778dc66b 100644
--- a/src/data/composite/control-flow/index.js
+++ b/src/data/composite/control-flow/index.js
@@ -10,6 +10,7 @@ export {default as exposeDependency} from './exposeDependency.js';
 export {default as exposeDependencyOrContinue} from './exposeDependencyOrContinue.js';
 export {default as exposeUpdateValueOrContinue} from './exposeUpdateValueOrContinue.js';
 export {default as exposeWhetherDependencyAvailable} from './exposeWhetherDependencyAvailable.js';
+export {default as flipFilter} from './flipFilter.js';
 export {default as raiseOutputWithoutDependency} from './raiseOutputWithoutDependency.js';
 export {default as raiseOutputWithoutUpdateValue} from './raiseOutputWithoutUpdateValue.js';
 export {default as withAvailabilityFilter} from './withAvailabilityFilter.js';
diff --git a/src/data/composite/control-flow/withAvailabilityFilter.js b/src/data/composite/control-flow/withAvailabilityFilter.js
index cfea998e..fd93af71 100644
--- a/src/data/composite/control-flow/withAvailabilityFilter.js
+++ b/src/data/composite/control-flow/withAvailabilityFilter.js
@@ -4,6 +4,7 @@
 // Accepts the same mode options as withResultOfAvailabilityCheck.
 //
 // See also:
+//  - flipFilter
 //  - withFilteredList
 //  - withResultOfAvailabilityCheck
 //