Add safer isArray function (#3606)

* Add safer isArray function

* Fix formatting

e2e/playwright/test-utils.ts

@@ -27,6 +27,7 @@ import {
 import * as TOML from '@iarna/toml'
 import { SaveSettingsPayload } from 'lib/settings/settingsTypes'
 import { SETTINGS_FILE_NAME } from 'lib/constants'
+import { isArray } from 'lib/utils'
 
 type TestColor = [number, number, number]
 export const TEST_COLORS = {
@@ -582,7 +583,7 @@ const _makeTemplate = (
   templateParts: TemplateStringsArray,
   ...options: TemplateOptions
 ) => {
-  const length = Math.max(...options.map((a) => (Array.isArray(a) ? a[0] : 0)))
+  const length = Math.max(...options.map((a) => (isArray(a) ? a[0] : 0)))
   let reExpTemplate = ''
   for (let i = 0; i < length; i++) {
     const currentStr = templateParts.map((str, index) => {
@@ -590,7 +591,7 @@ const _makeTemplate = (
       return (
         escapeRegExp(str) +
         String(
-          Array.isArray(currentOptions)
+          isArray(currentOptions)
             ? currentOptions[i]
             : typeof currentOptions === 'number'
             ? currentOptions

src/clientSideScene/sceneEntities.ts

@@ -75,7 +75,13 @@ import {
   changeSketchArguments,
   updateStartProfileAtArgs,
 } from 'lang/std/sketch'
-import { isOverlap, normaliseAngle, roundOff, throttle } from 'lib/utils'
+import {
+  isArray,
+  isOverlap,
+  normaliseAngle,
+  roundOff,
+  throttle,
+} from 'lib/utils'
 import {
   addStartProfileAt,
   createArrayExpression,
@@ -99,6 +105,7 @@ import {
 import { getThemeColorForThreeJs } from 'lib/theme'
 import { err, trap } from 'lib/trap'
 import { CSS2DObject } from 'three/examples/jsm/renderers/CSS2DRenderer'
+import { Point3d } from 'wasm-lib/kcl/bindings/Point3d'
 
 type DraftSegment = 'line' | 'tangentialArcTo'
 
@@ -116,6 +123,8 @@ export const SEGMENT_WIDTH_PX = 1.6
 export const HIDE_SEGMENT_LENGTH = 75 // in pixels
 export const HIDE_HOVER_SEGMENT_LENGTH = 60 // in pixels
 
+type Vec3Array = [number, number, number]
+
 // This singleton Class is responsible for all of the things the user sees and interacts with.
 // That mostly mean sketch elements.
 // Cameras, controls, raycasters, etc are handled by sceneInfra
@@ -384,7 +393,7 @@ export class SceneEntities {
     if (err(sketchGroup)) return Promise.reject(sketchGroup)
     if (!sketchGroup) return Promise.reject('sketchGroup not found')
 
-    if (!Array.isArray(sketchGroup?.value))
+    if (!isArray(sketchGroup?.value))
       return {
         truncatedAst,
         programMemoryOverride,
@@ -1838,6 +1847,7 @@ export function getSketchQuaternion(
   })
   if (err(sketchGroup)) return sketchGroup
   const zAxis = sketchGroup?.on.zAxis || sketchNormalBackUp
+  if (!zAxis) return Error('SketchGroup zAxis not found')
 
   return getQuaternionFromZAxis(massageFormats(zAxis))
 }
@@ -1962,8 +1972,6 @@ export function getQuaternionFromZAxis(zAxis: Vector3): Quaternion {
   return quaternion
 }
 
-function massageFormats(a: any): Vector3 {
+function massageFormats(a: Vec3Array | Point3d): Vector3 {
-  return Array.isArray(a)
+  return isArray(a) ? new Vector3(a[0], a[1], a[2]) : new Vector3(a.x, a.y, a.z)
-    ? new Vector3(a[0], a[1], a[2])
-    : new Vector3(a.x, a.y, a.z)
 }

src/lib/utils.ts

@@ -4,6 +4,13 @@ import { v4 } from 'uuid'
 
 export const uuidv4 = v4
 
+/**
+ * A safer type guard for arrays since the built-in Array.isArray() asserts `any[]`.
+ */
+export function isArray(val: any): val is unknown[] {
+  return Array.isArray(val)
+}
+
 export function isOverlap(a: SourceRange, b: SourceRange) {
   const [startingRange, secondRange] = a[0] < b[0] ? [a, b] : [b, a]
   const [lastOfFirst, firstOfSecond] = [startingRange[1], secondRange[0]]