improvement(salesforce): preserve picklist values and clear stale metadata on field type change

- custom field update now unions provided picklist values with the field's
  existing values instead of replacing the whole valueSet (no data loss)
- when fieldType changes on update, drop the prior type's type-specific
  metadata (length/precision/scale/visibleLines/valueSet/defaultValue/unique/
  externalId) and backfill the new type's required defaults

Author: waleedlatif1

apps/docs/content/docs/en/integrations/salesforce.mdx

@@ -1089,7 +1089,7 @@ Update an existing custom field on a Salesforce object using the Tooling API
 | `defaultValue` | string | No | Default value; for Checkbox fields use true or false |
 | `description` | string | No | Internal description of the field |
 | `inlineHelpText` | string | No | Help text shown next to the field in the UI |
-| `picklistValues` | string | No | Comma-separated values for Picklist or MultiselectPicklist fields |
+| `picklistValues` | string | No | Comma-separated values to add to a Picklist or MultiselectPicklist field \(existing values are kept\) |
 
 #### Output
 

apps/sim/tools/salesforce/update_custom_field.ts

@@ -126,7 +126,8 @@ export const salesforceUpdateCustomFieldTool: ToolConfig<
       type: 'string',
       required: false,
       visibility: 'user-or-llm',
-      description: 'Comma-separated values for Picklist or MultiselectPicklist fields',
+      description:
+        'Comma-separated values to add to a Picklist or MultiselectPicklist field (existing values are kept)',
     },
   },
 

apps/sim/tools/salesforce/utils.ts

@@ -172,15 +172,44 @@ function applyProvidedFieldMetadata(
 
   const picklistValues = parseDelimitedList(params.picklistValues)
   if (picklistValues.length > 0) {
+    // Union with any existing values so an update adds new options without
+    // dropping the field's current values (or their default flags).
+    const existingValues: Array<Record<string, any>> = Array.isArray(
+      target.valueSet?.valueSetDefinition?.value
+    )
+      ? target.valueSet.valueSetDefinition.value
+      : []
+    const existingFullNames = new Set(existingValues.map((entry) => entry.fullName))
+    const additions = picklistValues
+      .filter((value) => !existingFullNames.has(value))
+      .map((value) => ({ fullName: value, default: false, label: value }))
     target.valueSet = {
+      ...(target.valueSet ?? {}),
       valueSetDefinition: {
-        sorted: false,
-        value: picklistValues.map((value) => ({ fullName: value, default: false, label: value })),
+        ...(target.valueSet?.valueSetDefinition ?? {}),
+        sorted: target.valueSet?.valueSetDefinition?.sorted ?? false,
+        value: [...existingValues, ...additions],
       },
     }
   }
 }
 
+/**
+ * Type-specific metadata keys that do not carry across a field type change and
+ * must be dropped when the type changes, so stale dimensions (e.g. a Text
+ * `length` on a Checkbox) are not sent back to Salesforce.
+ */
+const TYPE_SPECIFIC_METADATA_KEYS = [
+  'length',
+  'precision',
+  'scale',
+  'visibleLines',
+  'valueSet',
+  'defaultValue',
+  'unique',
+  'externalId',
+] as const
+
 /**
  * Applies type-specific defaults required by Salesforce when the caller did not
  * supply them, so common field types work out of the box on create.
@@ -255,7 +284,21 @@ export function mergeCustomFieldMetadata(
   params: CustomFieldMetadataInput
 ): Record<string, any> {
   const metadata: Record<string, any> = { ...(existing ?? {}) }
+
+  const newType = params.fieldType?.trim()
+  const typeChanged = Boolean(newType && existing?.type && newType !== existing.type)
+  if (typeChanged) {
+    // Changing the type invalidates the previous type's dimensions; drop them so
+    // the PATCH does not carry stale metadata. Type-agnostic properties (label,
+    // description, help text, required) are preserved.
+    for (const key of TYPE_SPECIFIC_METADATA_KEYS) delete metadata[key]
+  }
+
   applyProvidedFieldMetadata(metadata, params)
+
+  // Backfill any properties the new type requires that the caller didn't supply.
+  if (typeChanged) applyFieldTypeDefaults(metadata)
+
   return metadata
 }