Editor: field hints show the column's raw data type, not the encoding type

src/app/services/spec-dataset-hints.ts

@@ -10,8 +10,11 @@
  *   - **Hover** — a column's inferred type + cardinality/range (from the stored
  *     profile); over a `calculate`/`filter`/`expr` string, a live validity check
  *     via core/expr-validate. Monaco merges these with the schema's own hovers.
- *   - **Inlay hints** — a faint `: <type>` beside each `field`, annotation without
- *     touching the text.
+ *   - **Inlay hints** — a faint `·<data-type>` beside each `field` (the column's
+ *     raw type: number/string/date/boolean), annotation without touching the text.
+ *     Deliberately the *data* type, not the encoding `type` — they share the line,
+ *     so a `: quantitative` here would read as annotating the adjacent `"type"`,
+ *     which the hint never describes.
  *
  * All three read the active draft's bound dataset (services/active-dataset) and
  * the cursor's JSON context (core/spec-cursor) at provide-time via `getState()` —
@@ -22,10 +25,8 @@
  */
 
 import * as monaco from 'monaco-editor/esm/vs/editor/edcore.main';
-import { defaultFieldType } from '@core/chart-builder';
 import { validateExpression } from '@core/expr-validate';
 import { stringValueAtOffset, valueKeyAtOffset } from '@core/spec-cursor';
-import type { ColumnType } from '@core/type-inference';
 import { useSnippetStore } from '../stores/SnippetStore';
 import {
   availableFieldsAt,
@@ -40,15 +41,14 @@ const FIELD_KEYS = new Set(['field', 'groupby']);
 /** Property values that hold a Vega expression (where the validity check fires). */
 const EXPR_KEYS = new Set(['calculate', 'filter', 'expr']);
 
-/** A short type label for a source field; null type (derived) is shown elsewhere. */
-const typeLabel = (type: ColumnType): string => defaultFieldType(type);
-
 /** Markdown hover for a field hint: type + stats for source, a note for derived. */
 function fieldHoverContents(hint: FieldHint, info: DataInfo): { value: string }[] {
   if (hint.derived || hint.type === null) {
     return [{ value: `**${hint.name}** · _derived by a transform_` }];
   }
-  const lines = [`**${hint.name}** · \`${typeLabel(hint.type)}\``];
+  // The column's raw data type (number/string/date/boolean) — same vocabulary as
+  // the inlay hint, not the Vega-Lite encoding `type` the user declares.
+  const lines = [`**${hint.name}** · \`${hint.type}\``];
   const stat = info.columnStats.find((s) => s.name === hint.name);
   if (stat) {
     if (stat.numericExtent)
@@ -91,7 +91,7 @@ export function configureSpecDatasetHints(): void {
           kind: f.derived
             ? monaco.languages.CompletionItemKind.Variable
             : monaco.languages.CompletionItemKind.Field,
-          detail: f.derived || f.type === null ? 'derived field' : typeLabel(f.type),
+          detail: f.derived || f.type === null ? 'derived field' : f.type,
           insertText: f.name,
           range,
         })),
@@ -167,7 +167,11 @@ export function configureSpecDatasetHints(): void {
         if (!type) continue; // unknown or derived (no type to annotate)
         hints.push({
           position: { lineNumber: line, column: match.index + match[0].length + 1 },
-          label: `: ${typeLabel(type)}`,
+          // The column's raw data type (number/string/date/boolean), not the
+          // Vega-Lite encoding `type`: a `: quantitative` here would read as an
+          // annotation of the adjacent `"type"`, which the hint never describes.
+          // The leading `·` marks it as a data fact about the field, not JSON syntax.
+          label: `·${type}`,
           kind: monaco.languages.InlayHintKind.Type,
           paddingLeft: true,
         });