3 files changed, 133 insertions, 0 deletions
diff --git a/src/data/composite/wiki-data/helpers/withDirectoryFromName.js b/src/data/composite/wiki-data/helpers/withDirectoryFromName.js
new file mode 100644
index 00000000..f85dae16
--- /dev/null
+++ b/src/data/composite/wiki-data/helpers/withDirectoryFromName.js
@@ -0,0 +1,41 @@
+// Compute a directory from a name.
+
+import {input, templateCompositeFrom} from '#composite';
+
+import {isName} from '#validators';
+import {getKebabCase} from '#wiki-data';
+
+import {raiseOutputWithoutDependency} from '#composite/control-flow';
+
+export default templateCompositeFrom({
+  annotation: `withDirectoryFromName`,
+
+  inputs: {
+    name: input({
+      validate: isName,
+      acceptsNull: true,
+    }),
+  },
+
+  outputs: ['#directory'],
+
+  steps: () => [
+    raiseOutputWithoutDependency({
+      dependency: input('name'),
+      mode: input.value('falsy'),
+      output: input.value({
+        ['#directory']: null,
+      }),
+    }),
+
+    {
+      dependencies: [input('name')],
+      compute: (continuation, {
+        [input('name')]: name,
+      }) => continuation({
+        ['#directory']:
+          getKebabCase(name),
+      }),
+    },
+  ],
+});
diff --git a/src/data/composite/wiki-data/helpers/withResolvedReverse.js b/src/data/composite/wiki-data/helpers/withResolvedReverse.js
new file mode 100644
index 00000000..818f60b7
--- /dev/null
+++ b/src/data/composite/wiki-data/helpers/withResolvedReverse.js
@@ -0,0 +1,40 @@
+// Actually execute a reverse function.
+
+import {input, templateCompositeFrom} from '#composite';
+
+import inputWikiData from '../inputWikiData.js';
+
+export default templateCompositeFrom({
+  annotation: `withReverseReferenceList`,
+
+  inputs: {
+    data: inputWikiData({allowMixedTypes: true}),
+    reverse: input({type: 'function'}),
+    options: input({type: 'object', defaultValue: null}),
+  },
+
+  outputs: ['#resolvedReverse'],
+
+  steps: () => [
+    {
+      dependencies: [
+        input.myself(),
+        input('data'),
+        input('reverse'),
+        input('options'),
+      ],
+
+      compute: (continuation, {
+        [input.myself()]: myself,
+        [input('data')]: data,
+        [input('reverse')]: reverseFunction,
+        [input('options')]: opts,
+      }) => continuation({
+        ['#resolvedReverse']:
+          (data
+            ? reverseFunction(myself, data, opts)
+            : reverseFunction(myself, opts)),
+      }),
+    },
+  ],
+});
diff --git a/src/data/composite/wiki-data/helpers/withSimpleDirectory.js b/src/data/composite/wiki-data/helpers/withSimpleDirectory.js
new file mode 100644
index 00000000..08ca3bfc
--- /dev/null
+++ b/src/data/composite/wiki-data/helpers/withSimpleDirectory.js
@@ -0,0 +1,52 @@
+// A "simple" directory, based only on the already-provided directory, if
+// available, or the provided name.
+
+import {input, templateCompositeFrom} from '#composite';
+
+import {isDirectory, isName} from '#validators';
+
+import {withResultOfAvailabilityCheck} from '#composite/control-flow';
+
+import withDirectoryFromName from './withDirectoryFromName.js';
+
+export default templateCompositeFrom({
+  annotation: `withSimpleDirectory`,
+
+  inputs: {
+    directory: input({
+      validate: isDirectory,
+      defaultDependency: 'directory',
+      acceptsNull: true,
+    }),
+
+    name: input({
+      validate: isName,
+      acceptsNull: true,
+    }),
+  },
+
+  outputs: ['#directory'],
+
+  steps: () => [
+    withResultOfAvailabilityCheck({
+      from: input('directory'),
+    }),
+
+    {
+      dependencies: ['#availability', input('directory')],
+      compute: (continuation, {
+        ['#availability']: availability,
+        [input('directory')]: directory,
+      }) =>
+        (availability
+          ? continuation.raiseOutput({
+              ['#directory']: directory
+            })
+          : continuation()),
+    },
+
+    withDirectoryFromName({
+      name: input('name'),
+    }),
+  ],
+});