fix(dashboards): show inclusive range end in exact caption and cover id/x-axis threshold lookups

Author: TheodoreSpeaks

apps/sim/lib/charts/annotations.test.ts

@@ -141,6 +141,31 @@ describe('chart annotations', () => {
     ).toThrow('Thresholds require a value axis')
   })
 
+  it('resolves a value axis selected by id, including a value x-axis on horizontal bars', () => {
+    const byId = applyChartAnnotations(
+      {
+        xAxis: { type: 'time' },
+        yAxis: [{ type: 'category' }, { id: 'latency', type: 'value' }],
+        series: [{ type: 'line', yAxisId: 'latency' }],
+      },
+      { thresholds: [{ value: 5 }] },
+      palette
+    )
+    expect((byId.series as Series[])[0].markLine).toMatchObject({ data: [{ yAxis: 5 }] })
+    const horizontal = applyChartAnnotations(
+      {
+        xAxis: [{ type: 'category' }, { id: 'count', type: 'value' }],
+        yAxis: [{ type: 'value' }, { id: 'stage', type: 'category', inverse: true }],
+        series: [{ type: 'bar', xAxisId: 'count', yAxisIndex: 1 }],
+      },
+      { thresholds: [{ value: 5, label: 'Limit' }] },
+      palette
+    )
+    const [first, labels] = horizontal.series as Series[]
+    expect(first.markLine).toMatchObject({ data: [{ xAxis: 5 }] })
+    expect(labels.markLine).toMatchObject({ data: [{ xAxis: 5, label: { position: 'start' } }] })
+  })
+
   it('rejects a first series that references an axis the chart does not define', () => {
     for (const reference of [{ yAxisIndex: 1 }, { yAxisIndex: -1 }, { yAxisIndex: 0.5 }])
       expect(() =>

apps/sim/lib/dashboards/time.test.ts

@@ -54,8 +54,7 @@ describe('dashboard time interactions', () => {
       { from: '2026-11-01T05:30:00.000Z', to: '2026-11-01T06:31:00.000Z' },
       'America/New_York'
     )
-    expect(text).toContain('01:30:00 EDT')
-    expect(text).toContain('01:31:00 EST')
+    expect(text).toBe('Nov 1, 01:30:00 EDT – Nov 1, 01:30:59 EST')
   })
 
   it('shows distinct endpoints for a sub-minute zoom range', () => {
@@ -64,6 +63,6 @@ describe('dashboard time interactions', () => {
         { from: '2026-09-20T14:30:00.000Z', to: '2026-09-20T14:30:01.000Z' },
         'UTC'
       )
-    ).toBe('Sep 20, 14:30:00 UTC – Sep 20, 14:30:01 UTC')
+    ).toBe('Sep 20, 14:30:00.000 UTC – Sep 20, 14:30:00.999 UTC')
   })
 })

apps/sim/lib/dashboards/time.ts

@@ -91,18 +91,22 @@ export function dashboardRangeText(range: DashboardTimeRange, timeZone: string):
   const toLocal = zonedWallClock(to, timeZone)
   if (fromLocal === toLocal) {
     // Same wall-clock minute (e.g. a DST fall-back repeat): formatRange would collapse both ends,
-    // so show the exact exclusive end to the second.
-    const exact = new Intl.DateTimeFormat('en-US', {
-      timeZone,
-      month: 'short',
-      day: 'numeric',
-      hour: '2-digit',
-      minute: '2-digit',
-      second: '2-digit',
-      hourCycle: 'h23',
-      timeZoneName: 'short',
-    })
-    return `${exact.format(from)} – ${exact.format(new Date(range.to))}`
+    // so show each inclusive end exactly, down to milliseconds if seconds still collide.
+    const exact = (fractionalSecondDigits?: 3) =>
+      new Intl.DateTimeFormat('en-US', {
+        timeZone,
+        month: 'short',
+        day: 'numeric',
+        hour: '2-digit',
+        minute: '2-digit',
+        second: '2-digit',
+        fractionalSecondDigits,
+        hourCycle: 'h23',
+        timeZoneName: 'short',
+      })
+    const seconds = exact()
+    const format = seconds.format(from) === seconds.format(to) ? exact(3) : seconds
+    return `${format.format(from)} – ${format.format(to)}`
   }
   const sameDay = fromLocal.slice(0, 10) === toLocal.slice(0, 10)
   return new Intl.DateTimeFormat('en-US', {