github.com/spf13/cast v1.10.0: ToFloat64

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify github.com/spf13/cast.ToFloat64 in pkg:golang/github.com/spf13/cast@v1.10.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/spf13/cast@v1.10.0
Demonstrate these symbols/APIs:
  - github.com/spf13/cast.ToFloat64

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

package sample

import (
	"github.com/spf13/cast"
)

// ToFloat64 converts any compatible value to float64 using cast.ToFloat64.
func ToFloat64(v any) float64 {
	return cast.ToFloat64(v)
}

// ToFloat64E converts any compatible value to float64 using cast.ToFloat64E, returning an error on failure.
func ToFloat64E(v any) (float64, error) {
	return cast.ToFloat64E(v)
}

package sample

import (
	"encoding/json"
	"math"
	"testing"

	"github.com/spf13/cast"
)

func TestToFloat64_Floats(t *testing.T) {
	val64 := 123.456
	if got := cast.ToFloat64(val64); got != val64 {
		t.Fatalf("cast.ToFloat64(%v) = %v; want %v", val64, got, val64)
	}
	gotE64, err := cast.ToFloat64E(val64)
	if err != nil || gotE64 != val64 {
		t.Fatalf("cast.ToFloat64E(%v) = (%v, %v); want (%v, nil)", val64, gotE64, err, val64)
	}

	val32 := float32(78.5)
	if got := cast.ToFloat64(val32); got != float64(val32) {
		t.Fatalf("cast.ToFloat64(%v) = %v; want %v", val32, got, float64(val32))
	}
	gotE32, err := cast.ToFloat64E(val32)
	if err != nil || gotE32 != float64(val32) {
		t.Fatalf("cast.ToFloat64E(%v) = (%v, %v); want (%v, nil)", val32, gotE32, err, float64(val32))
	}
}

func TestToFloat64_Integers(t *testing.T) {
	cases := []struct {
		input any
		want  float64
	}{
		{int(42), 42.0},
		{int8(-8), -8.0},
		{int16(1600), 1600.0},
		{int32(-32000), -32000.0},
		{int64(64000000), 64000000.0},
		{uint(42), 42.0},
		{uint8(8), 8.0},
		{uint16(1600), 1600.0},
		{uint32(32000), 32000.0},
		{uint64(64000000), 64000000.0},
		{0, 0.0},
	}

	for _, tc := range cases {
		if got := cast.ToFloat64(tc.input); got != tc.want {
			t.Fatalf("cast.ToFloat64(%T(%v)) = %v; want %v", tc.input, tc.input, got, tc.want)
		}
		gotE, err := cast.ToFloat64E(tc.input)
		if err != nil || gotE != tc.want {
			t.Fatalf("cast.ToFloat64E(%T(%v)) = (%v, %v); want (%v, nil)", tc.input, tc.input, gotE, err, tc.want)
		}
	}
}

func TestToFloat64_Booleans(t *testing.T) {
	if got := cast.ToFloat64(true); got != 1.0 {
		t.Fatalf("cast.ToFloat64(true) = %v; want 1.0", got)
	}
	if gotE, err := cast.ToFloat64E(true); err != nil || gotE != 1.0 {
		t.Fatalf("cast.ToFloat64E(true) = (%v, %v); want (1.0, nil)", gotE, err)
	}

	if got := cast.ToFloat64(false); got != 0.0 {
		t.Fatalf("cast.ToFloat64(false) = %v; want 0.0", got)
	}
	if gotE, err := cast.ToFloat64E(false); err != nil || gotE != 0.0 {
		t.Fatalf("cast.ToFloat64E(false) = (%v, %v); want (0.0, nil)", gotE, err)
	}
}

func TestToFloat64_StringsAndJsonNumber(t *testing.T) {
	strCases := []struct {
		input string
		want  float64
	}{
		{"3.14159", 3.14159},
		{"-42.5", -42.5},
		{"1e3", 1000.0},
		{"0", 0.0},
		{"-0.0", 0.0},
	}

	for _, tc := range strCases {
		if got := cast.ToFloat64(tc.input); math.Abs(got-tc.want) > 1e-9 {
			t.Fatalf("cast.ToFloat64(%q) = %v; want %v", tc.input, got, tc.want)
		}
		gotE, err := cast.ToFloat64E(tc.input)
		if err != nil || math.Abs(gotE-tc.want) > 1e-9 {
			t.Fatalf("cast.ToFloat64E(%q) = (%v, %v); want (%v, nil)", tc.input, gotE, err, tc.want)
		}
	}

	jn := json.Number("99.99")
	if got := cast.ToFloat64(jn); got != 99.99 {
		t.Fatalf("cast.ToFloat64(json.Number(%q)) = %v; want 99.99", jn, got)
	}
	gotEJN, err := cast.ToFloat64E(jn)
	if err != nil || gotEJN != 99.99 {
		t.Fatalf("cast.ToFloat64E(json.Number(%q)) = (%v, %v); want (99.99, nil)", jn, gotEJN, err)
	}
}

func TestToFloat64_Nil(t *testing.T) {
	if got := cast.ToFloat64(nil); got != 0.0 {
		t.Fatalf("cast.ToFloat64(nil) = %v; want 0.0", got)
	}
	gotE, err := cast.ToFloat64E(nil)
	if err != nil || gotE != 0.0 {
		t.Fatalf("cast.ToFloat64E(nil) = (%v, %v); want (0.0, nil)", gotE, err)
	}
}

func TestToFloat64_Pointers(t *testing.T) {
	f := 2.71828
	if got := cast.ToFloat64(&f); got != f {
		t.Fatalf("cast.ToFloat64(&float64) = %v; want %v", got, f)
	}

	i := 100
	if got := cast.ToFloat64(&i); got != 100.0 {
		t.Fatalf("cast.ToFloat64(&int) = %v; want 100.0", got)
	}

	s := "12.34"
	if got := cast.ToFloat64(&s); got != 12.34 {
		t.Fatalf("cast.ToFloat64(&string) = %v; want 12.34", got)
	}
}

func TestToFloat64_Invalid(t *testing.T) {
	invalidCases := []any{
		"not-a-number",
		[]int{1, 2},
		map[string]int{"a": 1},
		struct{ Name string }{Name: "test"},
	}

	for _, c := range invalidCases {
		if got := cast.ToFloat64(c); got != 0.0 {
			t.Fatalf("cast.ToFloat64(%v) = %v; want 0.0", c, got)
		}
		if _, err := cast.ToFloat64E(c); err == nil {
			t.Fatalf("cast.ToFloat64E(%v) expected error, got nil", c)
		}
	}
}

func TestToFloat64_Helper(t *testing.T) {
	cases := []any{
		123,
		"456.78",
		true,
		nil,
	}
	for _, c := range cases {
		expected := cast.ToFloat64(c)
		if got := ToFloat64(c); got != expected {
			t.Fatalf("ToFloat64(%v) = %v; want %v", c, got, expected)
		}
		expectedE, expectedErr := cast.ToFloat64E(c)
		gotE, err := ToFloat64E(c)
		if (err != nil) != (expectedErr != nil) || gotE != expectedE {
			t.Fatalf("ToFloat64E(%v) = (%v, %v); want (%v, %v)", c, gotE, err, expectedE, expectedErr)
		}
	}
}

{"case":{"caseId":"case:sha256:678f9d3d257f1553ae9106e9e42a1e4892610ad0438ace1f533243131cf49132","contract":["cast.ToFloat64 returns unchanged float64 when passed float64 and converts float32 to float64","cast.ToFloat64 and cast.ToFloat64E convert signed and unsigned integers to float64","cast.ToFloat64 and cast.ToFloat64E convert boolean values true to 1.0 and false to 0.0","cast.ToFloat64 and cast.ToFloat64E parse valid numeric strings and json.Number into float64","cast.ToFloat64 returns 0.0 and cast.ToFloat64E returns nil error for nil values","cast.ToFloat64 unwraps pointer values before converting their underlying values to float64","cast.ToFloat64 returns 0.0 and cast.ToFloat64E returns an error for non-numeric strings and unsupported types","ToFloat64 converts arbitrary values to float64 using cast.ToFloat64"],"goal":"verify github.com/spf13/cast.ToFloat64 in pkg:golang/github.com/spf13/cast@v1.10.0","kind":"HOW","packages":["pkg:golang/github.com/spf13/cast@v1.10.0"],"schemaVersion":1,"symbols":["github.com/spf13/cast.ToFloat64"]},"contractCommand":["go","test","./..."],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/spf13/cast@v1.10.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/spf13/cast@v1.10.0","symbols":["github.com/spf13/cast.ToFloat64"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.26.6

require github.com/spf13/cast v1.10.0

github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
github.com/spf13/cast v1.10.0 h1:h2x0u2shc1QuLHfxi+cTJvs30+ZAHOGRic8uyGTDWxY=
github.com/spf13/cast v1.10.0/go.mod h1:jNfB8QC9IA6ZuY2ZjDp0KtFO2LZZlg4S/7bzP6qqeHo=

{
  "schemaVersion": 1,
  "goal": "verify github.com/spf13/cast.ToFloat64 in pkg:golang/github.com/spf13/cast@v1.10.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/spf13/cast@v1.10.0"
  ],
  "symbols": [
    "github.com/spf13/cast.ToFloat64"
  ]
}