allow fields/presets to reference the locationSet from other files

Author: k-yle

README.md

@@ -368,6 +368,11 @@ See the [location-conflation](https://github.com/ideditor/location-conflation) p
 }
 ```
 
+Alternatively, a string can be used to reference the `locationSet` from another field or preset:
+```json
+"locationSet": "{presets/man_made/crane}"
+```
+
 ##### `replacement`
 
 The ID of a preset that is preferable to this one. iD's validator will flag features matching this preset and recommend that the user upgrade the tags.
@@ -677,6 +682,11 @@ See the [location-conflation](https://github.com/ideditor/location-conflation) p
 }
 ```
 
+Alternatively, a string can be used to reference the `locationSet` from another field or preset:
+```json
+"locationSet": "{fields/crane/type}"
+```
+
 ##### `urlFormat`
 
 For `identifier` fields, the permalink URL of the external record. It must contain a `{value}` placeholder where the tag value will be inserted. For example:

lib/build.js

@@ -431,8 +431,18 @@ function generateTranslations(fields, presets, tstrings, searchableFieldIDs) {
       }
     });
 
-    if (field.locationSet?.include) {
-      yamlField['#label'] += ` | Local preset for countries ${field.locationSet.include.map(country => `"${country.toUpperCase()}"`).join(', ')}`;
+    if (field.locationSet) {
+      const dereferenced = typeof field.locationSet === 'string'
+        ? dereference(field.locationSet, presets, fields)
+        : field;
+      const { locationSet } = dereferenced;
+
+      if (locationSet.include) {
+        yamlField['#label'] += ` | Local preset for countries ${locationSet.include.map(country => `"${country.toUpperCase()}"`).join(', ')}`;
+      }
+      if (locationSet.exclude) {
+        yamlField['#label'] += ` | Hidden in some countries: ${locationSet.exclude.map(country => `"${country.toUpperCase()}"`).join(', ')}`;
+      }
     }
 
     if (yamlField.placeholder) {
@@ -470,7 +480,7 @@ function generateTranslations(fields, presets, tstrings, searchableFieldIDs) {
       yamlPreset['#name'] += ' | Translate the primary name. Optionally, add equivalent synonyms on newlines in order of preference (press the Return key).';
     }
 
-    if (preset.locationSet?.include) {
+    if (typeof preset.locationSet === 'object' && preset.locationSet?.include) {
       yamlPreset['#name'] += ` | Local preset for countries ${preset.locationSet.include.map(country => `"${country.toUpperCase()}"`).join(', ')}`;
     }
 
@@ -761,6 +771,40 @@ function validateCategoryPresets(categories, presets) {
   });
 }
 
+/**
+ * looks up a string formatted as `{fields/*}` or `{presets/*}`
+ * @param {string} string
+ */
+function dereference(string, allPresets, allFields) {
+  const [type, ...path] = string.slice(1, -1).split('/');
+
+  if (type === 'presets') return allPresets[path.join('/')];
+  if (type === 'fields') return allFields[path.join('/')];
+  return undefined;
+}
+
+/**
+ * @param {string} id - only for diagnostics
+ * @param {string} locationSet
+ */
+function dereferenceLocationSetReference(id, locationSet, presets, fields) {
+  const match = dereference(locationSet, presets, fields);
+
+  if (!match) {
+    process.stderr.write(`${id}’s locationSet “${locationSet}” refers to a non-existant file.`);
+    process.stdout.write('\n');
+    process.exit(1);
+  }
+
+  if (!match.locationSet) {
+    process.stderr.write(`${id}’s locationSet “${locationSet}” references to a file which has no locationSet.`);
+    process.stdout.write('\n');
+    process.exit(1);
+  }
+
+  return match.locationSet;
+}
+
 function validatePresetFields(presets, fields) {
   const betweenBracketsRegex = /([^{]*?)(?=\})/;
   const maxFieldsBeforeError = 10;
@@ -785,6 +829,10 @@ function validatePresetFields(presets, fields) {
       }
     }
 
+    if (typeof preset.locationSet === 'string') {
+      preset.locationSet = dereferenceLocationSetReference(presetID, preset.locationSet, presets, fields);
+    }
+
     // the keys for properties that contain arrays of field ids
     let fieldKeys = ['fields', 'moreFields'];
     for (let fieldsKeyIndex in fieldKeys) {
@@ -849,11 +897,19 @@ function validatePresetFields(presets, fields) {
   }
 
   for (let fieldID in fields) {
+    const field = fields[fieldID];
     if (!usedFieldIDs.has(fieldID) &&
         fields[fieldID].universal !== true &&
         (fields[fieldID].usage || 'preset') === 'preset') {
       process.stdout.write('Field "' + fields[fieldID].label + '" (' + fieldID + ') isn\'t used by any presets.\n');
     }
+
+    if (typeof field.locationSet === 'string') {
+      // we could overide `field.locationSet` with the response from this function,
+      // so that data consumers don't have to do any work.
+      // But we won't do that, to be consistent with existing fields.
+      dereferenceLocationSetReference(fieldID, field.locationSet, presets, fields);
+    }
   }
 }
 

schemas/field.json

@@ -311,29 +311,38 @@
             }
         },
         "locationSet": {
-            "description": "An object specifying the IDs of regions where this field is or isn't valid. See: https://github.com/ideditor/location-conflation",
-            "type": "object",
-            "minProperties": 1,
-            "properties": {
-                "include": {
-                    "type": "array",
-                    "minItems": 1,
-                    "uniqueItems": true,
-                    "items": {
-                        "type": "string"
-                    }
+            "oneOf": [
+                {
+                    "description": "An object specifying the IDs of regions where this field is or isn't valid. See: https://github.com/ideditor/location-conflation",
+                    "type": "object",
+                    "minProperties": 1,
+                    "properties": {
+                        "include": {
+                            "type": "array",
+                            "minItems": 1,
+                            "uniqueItems": true,
+                            "items": {
+                                "type": "string"
+                            }
+                        },
+                        "exclude": {
+                            "type": "array",
+                            "minItems": 1,
+                            "uniqueItems": true,
+                            "items": {
+                                "type": "string"
+                            }
+                        }
+                    },
+                    "additionalProperties": false
                 },
-                "exclude": {
-                    "type": "array",
-                    "minItems": 1,
-                    "uniqueItems": true,
-                    "items": {
-                        "type": "string"
-                    }
+                {
+                    "description": "An string referencing another preset which has a locationSet",
+                    "type": "string",
+                    "pattern": "^\\{.+\\}$"
                 }
-            },
-            "additionalProperties": false
-        },
+            ]
+        } ,
         "urlFormat":  {
             "description": "Permalink URL for `identifier` fields. Must contain a {value} placeholder",
             "type": "string"