net/url: get file path error

[Dami-star]

What version of Go are you using (go version)?

$ go version
go version go1.18.1 linux/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE="on"
GOARCH="amd64"
GOBIN=""
GOCACHE="/root/.cache/go-build"
GOENV="/root/.config/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/root/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/root/go"
GOPRIVATE=""
GOPROXY="https://mirrors.aliyun.com/goproxy/"
GOROOT="/usr/local/go1.18.1"
GOSUMDB="off"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go1.18.1/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="go1.18.1"
GCCGO="/usr/local/gcc-12.1.0/bin/gccgo"
GOAMD64="v1"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/root/gosmith/bugReview/template0/go.mod"
GOWORK=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"

What did you do?

package main

import (
"fmt"
"net/url"
)

func main() {
u, _ := url.Parse("file:///home/dami/Desktop/%25.txt")
fmt.Println(u.Path)
}

What did you expect to see?

go run main.go
/home/dami/Desktop/%25.txt

What did you see instead?

go run main.go
/home/dami/Desktop/%.txt

[ZekeLu]

%25 is the percent-encoding of %. url.Parse() will unescape %25 to its original form %. So the result is correct.

See https://www.rfc-editor.org/rfc/rfc3986#section-2.4

Because the percent ("%") character serves as the indicator for percent-encoded octets, it must be percent-encoded as "%25" for that octet to be used as data within a URI.

[Dami-star]

Ok, thanks, if the actual file is %25.txt, the url should be file:///home/dami/Desktop/%2525.txt