1 files changed, 68 insertions, 0 deletions
diff --git a/src/data/composite/wiki-data/withClonedThings.js b/src/data/composite/wiki-data/withClonedThings.js
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+++ b/src/data/composite/wiki-data/withClonedThings.js
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+// Clones all the things in a list. If the 'assign' input is provided,
+// all new things are assigned the same specified properties. If the
+// 'assignEach' input is provided, each new thing is assigned the
+// corresponding properties.
+
+import CacheableObject from '#cacheable-object';
+import {input, templateCompositeFrom} from '#composite';
+import {isObject, sparseArrayOf} from '#validators';
+
+import {withMappedList} from '#composite/data';
+
+export default templateCompositeFrom({
+  annotation: `withClonedThings`,
+
+  inputs: {
+    things: input({type: 'array'}),
+
+    assign: input({
+      type: 'object',
+      defaultValue: null,
+    }),
+
+    assignEach: input({
+      validate: sparseArrayOf(isObject),
+      defaultValue: null,
+    }),
+  },
+
+  outputs: ['#clonedThings'],
+
+  steps: () => [
+    {
+      dependencies: [input('assign'), input('assignEach')],
+      compute: (continuation, {
+        [input('assign')]: assign,
+        [input('assignEach')]: assignEach,
+      }) => continuation({
+        ['#assignmentMap']:
+          (index) =>
+            (assign && assignEach
+              ? {...assignEach[index] ?? {}, ...assign}
+           : assignEach
+              ? assignEach[index] ?? {}
+              : assign ?? {}),
+      }),
+    },
+
+    {
+      dependencies: ['#assignmentMap'],
+      compute: (continuation, {
+        ['#assignmentMap']: assignmentMap,
+      }) => continuation({
+        ['#cloningMap']:
+          (thing, index) =>
+            Object.assign(
+              CacheableObject.clone(thing),
+              assignmentMap(index)),
+      }),
+    },
+
+    withMappedList({
+      list: input('things'),
+      map: '#cloningMap',
+    }).outputs({
+      '#mappedList': '#clonedThings',
+    }),
+  ],
+});