Document nicestNumberBetween()

caphadoop · Nov 24, 2022 · 7899f8a · 7899f8a
1 parent 5ee13a2
commit 7899f8a
Show file tree

Hide file tree

Showing 3 changed files with 179 additions and 173 deletions.
diff --git a/theatre/shared/src/utils/niceNumberUtils.test.ts b/theatre/shared/src/utils/niceNumberUtils.test.ts
@@ -0,0 +1,158 @@
+import {
+  getLastMultipleOf,
+  numberOfDecimals,
+  nicestFloatBetween,
+  nicestIntegerBetween,
+  nicestNumberBetween,
+  toPrecision,
+} from './niceNumberUtils'
+import type {$IntentionalAny} from './types'
+
+const example = <Args extends $IntentionalAny[], Return>(
+  fn: (...args: Args) => Return,
+  args: Args,
+  expectation: Return,
+  opts: Partial<{skip: boolean; debug: boolean}> = {},
+) => {
+  ;(opts.skip ? it.skip : it)(
+    `${fn.name}(${args.join(', ')}) => ${expectation}`,
+    () => {
+      // @ts-expect-error @ignore
+      if (opts.debug) global.dbg = true
+      const val = fn(...args)
+      // @ts-expect-error @ignore
+      global.dbg = false
+      expect(val).toEqual(expectation)
+    },
+  )
+}
+
+describe(`niceNumberUtils()`, () => {
+  describe(`nicestNumberBetween()`, () => {
+    example(nicestNumberBetween, [0.1, 1.1], 1)
+    example(nicestNumberBetween, [0.1111111123, 0.2943439448], 0.25)
+    example(nicestNumberBetween, [0.19, 0.23], 0.2)
+    example(nicestNumberBetween, [-0.19, 0.23], 0)
+    example(nicestNumberBetween, [-0.19, -0.02], -0.1, {debug: false})
+    example(nicestNumberBetween, [-0.19, -0.022], -0.1, {debug: false})
+    example(nicestNumberBetween, [-0.19, -0.022234324], -0.1, {
+      debug: false,
+    })
+    example(nicestNumberBetween, [-0.19, 0.0222222], 0)
+    example(nicestNumberBetween, [-0.19, 0.02], 0)
+    example(
+      nicestNumberBetween,
+      [22304.2398427391, 22304.2398427393],
+      22304.2398427392,
+    )
+    example(nicestNumberBetween, [22304.2398427391, 22304.4], 22304.25)
+    example(nicestNumberBetween, [902, 901], 902)
+    example(nicestNumberBetween, [-10, -5], -10)
+    example(nicestNumberBetween, [-5, -10], -10)
+    example(nicestNumberBetween, [-10, -5], -10)
+    example(
+      nicestNumberBetween,
+      [-0.00876370109231405, -2.909374013346118e-50],
+      0,
+      {debug: false},
+    )
+    example(
+      nicestNumberBetween,
+      [0.059449443526800295, 0.06682093143783596],
+      0.06,
+      {debug: false},
+    )
+    const getRandomNumber = () => {
+      const sign = Math.random() > 0.5 ? 1 : -1
+      return (
+        (Math.pow(Math.random(), Math.random()) /
+          Math.pow(10, Math.random() * 100)) *
+        sign
+      )
+    }
+    test(`nicestNumberBetween() => fuzzy`, () => {
+      for (let i = 0; i < 2000; i++) {
+        const from = toPrecision(getRandomNumber())
+        const to = toPrecision(getRandomNumber())
+
+        const result = nicestNumberBetween(from, to)
+        if (from < to) {
+          if (result < from || result > to) {
+            throw new Error(`Invalid: ${from} ${to} ${result}`)
+          }
+        } else {
+          if (result > from || result < to) {
+            throw new Error(`Invalid: ${to} ${from} ${result}`)
+          }
+        }
+      }
+    })
+  })
+  describe(`nicestIntegerBetween`, () => {
+    example(nicestIntegerBetween, [-1, 6], 0, {})
+    example(nicestIntegerBetween, [0, 6], 0, {})
+    example(nicestIntegerBetween, [-1, 0], 0, {})
+    example(nicestIntegerBetween, [-1850, -1740], -1750, {})
+    example(nicestIntegerBetween, [1, 6], 5, {})
+    example(nicestIntegerBetween, [1, 5], 5)
+    example(nicestIntegerBetween, [1, 2], 2)
+    example(nicestIntegerBetween, [1, 10], 10)
+    example(nicestIntegerBetween, [1, 12], 10)
+    example(nicestIntegerBetween, [11, 15], 15)
+    example(nicestIntegerBetween, [101, 102], 102, {debug: true})
+    example(nicestIntegerBetween, [11, 14, false], 12)
+    example(nicestIntegerBetween, [11, 14, true], 12.5)
+    example(nicestIntegerBetween, [11, 12], 12)
+    example(nicestIntegerBetween, [11, 12], 12, {})
+    example(nicestIntegerBetween, [10, 90], 50)
+    example(nicestIntegerBetween, [10, 100], 100)
+    example(nicestIntegerBetween, [10, 110], 100)
+    example(nicestIntegerBetween, [9, 100], 10)
+    example(nicestIntegerBetween, [9, 1100], 10)
+    example(nicestIntegerBetween, [9, 699], 10)
+    example(nicestIntegerBetween, [9, 400], 10)
+    example(nicestIntegerBetween, [9, 199], 10)
+    example(nicestIntegerBetween, [9, 1199], 10)
+    example(nicestIntegerBetween, [1921, 1998], 1950)
+    example(nicestIntegerBetween, [1921, 2020], 2000)
+    example(nicestIntegerBetween, [1601, 1998], 1750)
+    example(nicestIntegerBetween, [1919, 1921], 1920)
+    example(nicestIntegerBetween, [1919, 1919], 1919)
+    example(nicestIntegerBetween, [3901, 3902], 3902)
+    example(nicestIntegerBetween, [901, 902], 902)
+  })
+  describe(`nicestFloatBetween()`, () => {
+    example(nicestFloatBetween, [0.19, 0.2122], 0.2)
+    example(nicestFloatBetween, [0.19, 0.31], 0.25)
+    example(nicestFloatBetween, [0.19, 0.41], 0.25)
+    example(nicestFloatBetween, [0.19, 1.9], 0.5)
+  })
+  describe(`numberOfDecimals()`, () => {
+    example(numberOfDecimals, [1.1], 1)
+    example(numberOfDecimals, [1.12], 2)
+    example(numberOfDecimals, [1], 0)
+    example(numberOfDecimals, [10], 0)
+    example(numberOfDecimals, [0.1 + 0.2], 1)
+    example(numberOfDecimals, [0.12399993], 8)
+    example(numberOfDecimals, [0.12399993], 8)
+    example(numberOfDecimals, [0.123999931], 9)
+    example(numberOfDecimals, [0.1239999312], 10)
+    example(numberOfDecimals, [0.12399993121], 10)
+  })
+
+  describe(`toPrecision()`, () => {
+    example(toPrecision, [1.1], 1.1)
+    example(toPrecision, [0.1 + 0.2], 0.3)
+    example(toPrecision, [0.3 - 0.3], 0)
+    example(toPrecision, [0.4 - 0.1], 0.3)
+    example(toPrecision, [1.4 - 0.1], 1.3)
+  })
+
+  describe(`getLastMultipleOf()`, () => {
+    example(getLastMultipleOf, [1, 10], 0)
+    example(getLastMultipleOf, [11, 10], 10)
+    example(getLastMultipleOf, [11, 5], 10)
+    example(getLastMultipleOf, [11, 2], 10)
+    example(getLastMultipleOf, [4, 2], 4)
+  })
+})
diff --git a/...e/shared/src/utils/numberRoundingUtils.ts → theatre/shared/src/utils/niceNumberUtils.ts b/...e/shared/src/utils/numberRoundingUtils.ts → theatre/shared/src/utils/niceNumberUtils.ts
@@ -2,46 +2,47 @@ import padEnd from 'lodash-es/padEnd'
 import logger from '@theatre/shared/logger'
 
 /**
- * Returns the _roundest_ number `c`, such that `a <= c <= b`. This is useful
- * when a number value is beinged "nudged" by a user, and we want to avoid setting
- * it to weird value like `101.1239293814314`, when we know that the user probably just meant `100`.
+ * Returns the _aesthetically pleasing_ (aka "nicest") number `c`, such that `a <= c <= b`.
+ * This is useful when a numeric value is being "nudged" by the user (e.g. dragged via mouse pointer),
+ * and we want to avoid setting it to weird value like `101.1239293814314`, when we know that the user
+ * probably just meant `100`.
  *
  * Examples
  * ```ts
- * roundestNumberBetween(0.1111111123, 0.2943439448) // 0.25
- * roundestNumberBetween(0.19, 0.23) // 0.2
- * roundestNumberBetween(1921, 1998) // 1950
- * roundestNumberBetween(10, 110) // 100
- * // There are many more examples at `./numberRoundingUtils.test.ts`
+ * nicestNumberBetween(0.1111111123, 0.2943439448) // 0.25
+ * nicestNumberBetween(0.19, 0.23) // 0.2
+ * nicestNumberBetween(1921, 1998) // 1950
+ * nicestNumberBetween(10, 110) // 100
+ * // There are more examples at `./niceNumberUtils.test.ts`
  * ```
  */
-export function roundestNumberBetween(_a: number, _b: number): number {
+export function nicestNumberBetween(_a: number, _b: number): number {
   if (_b < _a) {
-    return roundestNumberBetween(_b, _a)
+    return nicestNumberBetween(_b, _a)
   }
 
   if (_a < 0 && _b < 0) {
-    return noMinusZero(roundestNumberBetween(-_b, -_a) * -1)
+    return noMinusZero(nicestNumberBetween(-_b, -_a) * -1)
   }
 
   if (_a <= 0 && _b >= 0) return 0
 
   const aCeiling = Math.ceil(_a)
   if (aCeiling <= _b) {
-    return roundestIntegerBetween(aCeiling, Math.floor(_b))
+    return nicestIntegerBetween(aCeiling, Math.floor(_b))
   } else {
     const [a, b] = [_a, _b]
     const integer = Math.floor(a)
 
-    return integer + roundestFloat(a - integer, b - integer)
+    return integer + nicestFloatBetween(a - integer, b - integer)
   }
 }
 
 // const multiplesOfInterest = [10, 5, 4, 2]
 const halvesAndQuartiles = [5, 2.5, 7.5]
 const multipliersWithoutQuartiles = [5, 2, 4, 6, 8, 1, 3, 7, 9]
 
-export function roundestIntegerBetween(
+export function nicestIntegerBetween(
   _a: number,
   _b: number,
   decimalsAllowed: boolean = true,
@@ -138,9 +139,11 @@ export const stringifyNumber = (n: number): string => {
 }
 
 /**
+ * The float-specific version of {@link nicestNumberBetween}.
+ *
  * it is expected that both args are 0 \< arg \< 1
  */
-export const roundestFloat = (a: number, b: number): number => {
+export const nicestFloatBetween = (a: number, b: number): number => {
   const inString = {
     a: stringifyNumber(a),
     b: stringifyNumber(b),
@@ -173,14 +176,15 @@ export const roundestFloat = (a: number, b: number): number => {
     b: padEnd(withoutInteger.b, maxNumberOfDecimals, '0'),
   }
 
-  const roundestInt = roundestIntegerBetween(
+  const mostAestheticInt = nicestIntegerBetween(
     parseInt(withPaddedDecimals.a, 10) * Math.pow(10, maxNumberOfLeadingZeros),
     parseInt(withPaddedDecimals.b, 10) * Math.pow(10, maxNumberOfLeadingZeros),
     true,
   )
 
   return toPrecision(
-    roundestInt / Math.pow(10, maxNumberOfLeadingZeros + maxNumberOfDecimals),
+    mostAestheticInt /
+      Math.pow(10, maxNumberOfLeadingZeros + maxNumberOfDecimals),
   )
 }