Add Duration.divide (#2494)

Author: thewilkybarkid

.changeset/yellow-shirts-destroy.md

@@ -0,0 +1,18 @@
+---
+"effect": patch
+---
+
+Add `Duration.divide` and `Duration.unsafeDivide`.
+
+```ts
+import { Duration, Option } from "effect"
+import assert from "assert"
+
+assert.deepStrictEqual(Duration.divide("10 seconds", 2), Option.some(Duration.decode("5 seconds")))
+assert.deepStrictEqual(Duration.divide("10 seconds", 0), Option.none())
+assert.deepStrictEqual(Duration.divide("1 nano", 1.5), Option.none())
+
+assert.deepStrictEqual(Duration.unsafeDivide("10 seconds", 2), Duration.decode("5 seconds"))
+assert.deepStrictEqual(Duration.unsafeDivide("10 seconds", 0), Duration.infinity)
+assert.throws(() => Duration.unsafeDivide("1 nano", 1.5))
+```

packages/effect/dtslint/Duration.ts

@@ -110,6 +110,20 @@ Duration.max("1 minutes", "2 millis")
 // $ExpectType Duration
 Duration.clamp("1 millis", { minimum: "2 millis", maximum: "3 millis" })
 
+// -------------------------------------------------------------------------------------
+// divide
+// -------------------------------------------------------------------------------------
+
+// $ExpectType Option<Duration>
+Duration.divide("1 seconds", 2)
+
+// -------------------------------------------------------------------------------------
+// unsafeDivide
+// -------------------------------------------------------------------------------------
+
+// $ExpectType Duration
+Duration.unsafeDivide("1 seconds", 2)
+
 // -------------------------------------------------------------------------------------
 // times
 // -------------------------------------------------------------------------------------

packages/effect/src/Duration.ts

@@ -515,6 +515,59 @@ export const clamp: {
     })
 )
 
+/**
+ * @since 2.4.19
+ * @category math
+ */
+export const divide: {
+  (by: number): (self: DurationInput) => Option.Option<Duration>
+  (self: DurationInput, by: number): Option.Option<Duration>
+} = dual(
+  2,
+  (self: DurationInput, by: number): Option.Option<Duration> =>
+    match(self, {
+      onMillis: (millis) => {
+        if (by === 0 || isNaN(by) || !Number.isFinite(by)) {
+          return Option.none()
+        }
+        return Option.some(make(millis / by))
+      },
+      onNanos: (nanos) => {
+        if (isNaN(by) || by <= 0 || !Number.isFinite(by)) {
+          return Option.none()
+        }
+        try {
+          return Option.some(make(nanos / BigInt(by)))
+        } catch (e) {
+          return Option.none()
+        }
+      }
+    })
+)
+
+/**
+ * @since 2.4.19
+ * @category math
+ */
+export const unsafeDivide: {
+  (by: number): (self: DurationInput) => Duration
+  (self: DurationInput, by: number): Duration
+} = dual(
+  2,
+  (self: DurationInput, by: number): Duration =>
+    match(self, {
+      onMillis: (millis) => make(millis / by),
+      onNanos: (nanos) => {
+        if (isNaN(by) || by < 0 || Object.is(by, -0)) {
+          return zero
+        } else if (Object.is(by, 0) || !Number.isFinite(by)) {
+          return infinity
+        }
+        return make(nanos / BigInt(by))
+      }
+    })
+)
+
 /**
  * @since 2.0.0
  * @category math

packages/effect/test/Duration.test.ts

@@ -162,6 +162,48 @@ describe("Duration", () => {
     }))
   })
 
+  it("divide", () => {
+    expect(Duration.divide(Duration.minutes(1), 2)).toEqual(Option.some(Duration.seconds(30)))
+    expect(Duration.divide(Duration.seconds(1), 3)).toEqual(Option.some(Duration.nanos(333333333n)))
+    expect(Duration.divide(Duration.nanos(2n), 2)).toEqual(Option.some(Duration.nanos(1n)))
+    expect(Duration.divide(Duration.nanos(1n), 3)).toEqual(Option.some(Duration.zero))
+    expect(Duration.divide(Duration.infinity, 2)).toEqual(Option.some(Duration.infinity))
+    expect(Duration.divide(Duration.zero, 2)).toEqual(Option.some(Duration.zero))
+    expect(Duration.divide(Duration.minutes(1), 0)).toEqual(Option.none())
+    expect(Duration.divide(Duration.minutes(1), -0)).toEqual(Option.none())
+    expect(Duration.divide(Duration.nanos(1n), 0)).toEqual(Option.none())
+    expect(Duration.divide(Duration.nanos(1n), -0)).toEqual(Option.none())
+    expect(Duration.divide(Duration.minutes(1), 0.5)).toEqual(Option.some(Duration.minutes(2)))
+    expect(Duration.divide(Duration.minutes(1), 1.5)).toEqual(Option.some(Duration.seconds(40)))
+    expect(Duration.divide(Duration.minutes(1), NaN)).toEqual(Option.none())
+    expect(Duration.divide(Duration.nanos(1n), 0.5)).toEqual(Option.none())
+    expect(Duration.divide(Duration.nanos(1n), 1.5)).toEqual(Option.none())
+    expect(Duration.divide(Duration.nanos(1n), NaN)).toEqual(Option.none())
+
+    expect(Duration.divide("1 minute", 2)).toEqual(Option.some(Duration.seconds(30)))
+  })
+
+  it("unsafeDivide", () => {
+    expect(Duration.unsafeDivide(Duration.minutes(1), 2)).toEqual(Duration.seconds(30))
+    expect(Duration.unsafeDivide(Duration.seconds(1), 3)).toEqual(Duration.nanos(333333333n))
+    expect(Duration.unsafeDivide(Duration.nanos(2n), 2)).toEqual(Duration.nanos(1n))
+    expect(Duration.unsafeDivide(Duration.nanos(1n), 3)).toEqual(Duration.zero)
+    expect(Duration.unsafeDivide(Duration.infinity, 2)).toEqual(Duration.infinity)
+    expect(Duration.unsafeDivide(Duration.zero, 2)).toEqual(Duration.zero)
+    expect(Duration.unsafeDivide(Duration.minutes(1), 0)).toEqual(Duration.infinity)
+    expect(Duration.unsafeDivide(Duration.minutes(1), -0)).toEqual(Duration.zero)
+    expect(Duration.unsafeDivide(Duration.nanos(1n), 0)).toEqual(Duration.infinity)
+    expect(Duration.unsafeDivide(Duration.nanos(1n), -0)).toEqual(Duration.zero)
+    expect(Duration.unsafeDivide(Duration.minutes(1), 0.5)).toEqual(Duration.minutes(2))
+    expect(Duration.unsafeDivide(Duration.minutes(1), 1.5)).toEqual(Duration.seconds(40))
+    expect(Duration.unsafeDivide(Duration.minutes(1), NaN)).toEqual(Duration.zero)
+    expect(() => Duration.unsafeDivide(Duration.nanos(1n), 0.5)).toThrow()
+    expect(() => Duration.unsafeDivide(Duration.nanos(1n), 1.5)).toThrow()
+    expect(Duration.unsafeDivide(Duration.nanos(1n), NaN)).toEqual(Duration.zero)
+
+    expect(Duration.unsafeDivide("1 minute", 2)).toEqual(Duration.seconds(30))
+  })
+
   it("times", () => {
     expect(Duration.times(Duration.seconds(1), 60)).toEqual(Duration.minutes(1))
     expect(Duration.times(Duration.nanos(2n), 10)).toEqual(Duration.nanos(20n))