Fixed incorrect OS detection

src/asm/Finalize.go

@@ -31,11 +31,11 @@ func (a Assembler) Finalize(dlls dll.List) ([]byte, []byte) {
 	)
 
 	switch config.TargetOS {
-	case "linux":
+	case config.Linux:
 		headerEnd = elf.HeaderEnd
-	case "macos":
+	case config.Mac:
 		headerEnd = macho.HeaderEnd
-	case "windows":
+	case config.Windows:
 		headerEnd = pe.HeaderEnd
 	}
 
@@ -443,7 +443,7 @@ restart:
 		binary.LittleEndian.PutUint32(slice, uint32(address))
 	}
 
-	if config.TargetOS == "windows" {
+	if config.TargetOS == config.Windows {
 		if len(data) == 0 {
 			data = []byte{0}
 		}

src/build/Build.go

@@ -37,7 +37,7 @@ func (build *Build) Executable() string {
 		path = fromDirectoryName(path)
 	}
 
-	if config.TargetOS == "windows" {
+	if config.TargetOS == config.Windows {
 		path += ".exe"
 	}
 

src/cli/Build.go

@@ -3,6 +3,7 @@ package cli
 import (
 	"fmt"
 	"os"
+	"runtime"
 	"strings"
 
 	"git.akyoto.dev/cli/q/src/build"
@@ -60,7 +61,16 @@ func buildWithArgs(args []string) (*build.Build, error) {
 				return b, &errors.ExpectedCLIParameter{Parameter: "os"}
 			}
 
-			config.TargetOS = args[i]
+			switch args[i] {
+			case "linux":
+				config.TargetOS = config.Linux
+			case "mac":
+				config.TargetOS = config.Mac
+			case "windows":
+				config.TargetOS = config.Windows
+			default:
+				return b, &errors.InvalidParameterValue{Value: args[i], Parameter: "os"}
+			}
 
 		default:
 			if strings.HasPrefix(args[i], "-") {
@@ -71,6 +81,10 @@ func buildWithArgs(args []string) (*build.Build, error) {
 		}
 	}
 
+	if config.TargetOS == config.Unknown {
+		return b, &errors.InvalidParameterValue{Value: runtime.GOOS, Parameter: "os"}
+	}
+
 	if len(b.Files) == 0 {
 		b.Files = append(b.Files, ".")
 	}

src/compiler/Result.go

@@ -2,7 +2,6 @@ package compiler
 
 import (
 	"bufio"
-	"fmt"
 	"io"
 	"os"
 
@@ -38,15 +37,15 @@ func (r *Result) finalize() ([]byte, []byte, dll.List) {
 	final.Call("main.main")
 
 	switch config.TargetOS {
-	case "linux":
+	case config.Linux:
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[0], LinuxExit)
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[1], 0)
 		final.Syscall()
-	case "mac":
+	case config.Mac:
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[0], MacExit)
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[1], 0)
 		final.Syscall()
-	case "windows":
+	case config.Windows:
 		final.RegisterNumber(asm.MOVE, x64.WindowsInputRegisters[0], 0)
 		final.DLLCall("kernel32.ExitProcess")
 	}
@@ -70,15 +69,15 @@ func (r *Result) finalize() ([]byte, []byte, dll.List) {
 	final.Label(asm.LABEL, "_crash")
 
 	switch config.TargetOS {
-	case "linux":
+	case config.Linux:
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[0], LinuxExit)
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[1], 1)
 		final.Syscall()
-	case "mac":
+	case config.Mac:
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[0], MacExit)
 		final.RegisterNumber(asm.MOVE, x64.SyscallInputRegisters[1], 1)
 		final.Syscall()
-	case "windows":
+	case config.Windows:
 		final.RegisterNumber(asm.MOVE, x64.WindowsInputRegisters[0], 1)
 		final.DLLCall("kernel32.ExitProcess")
 	}
@@ -155,14 +154,12 @@ func write(writer io.Writer, code []byte, data []byte, dlls dll.List) error {
 	buffer := bufio.NewWriter(writer)
 
 	switch config.TargetOS {
-	case "linux":
+	case config.Linux:
 		elf.Write(buffer, code, data)
-	case "mac":
+	case config.Mac:
 		macho.Write(buffer, code, data)
-	case "windows":
+	case config.Windows:
 		pe.Write(buffer, code, data, dlls)
-	default:
-		return fmt.Errorf("unsupported platform '%s'", config.TargetOS)
 	}
 
 	return buffer.Flush()

src/config/config.go

@@ -27,7 +27,7 @@ var (
 	TargetArch string
 
 	// Target platform.
-	TargetOS string
+	TargetOS OS
 )
 
 // Reset resets the configuration to its default values.
@@ -36,9 +36,14 @@ func Reset() {
 	ConstantFold = true
 	Dry = false
 	TargetArch = runtime.GOARCH
-	TargetOS = runtime.GOOS
+	TargetOS = Unknown
 
-	if TargetOS == "darwin" {
+	switch runtime.GOOS {
-		TargetOS = "mac"
+	case "linux":
+		TargetOS = Linux
+	case "darwin":
+		TargetOS = Mac
+	case "windows":
+		TargetOS = Windows
 	}
 }

src/config/os.go

@@ -0,0 +1,10 @@
+package config
+
+type OS uint8
+
+const (
+	Unknown OS = iota
+	Linux
+	Mac
+	Windows
+)

src/errors/InvalidParameterValue.go

@@ -0,0 +1,14 @@
+package errors
+
+import "fmt"
+
+// InvalidParameterValue error is created when a parameter has an invalid value.
+type InvalidParameterValue struct {
+	Value     string
+	Parameter string
+}
+
+// Error generates the string representation.
+func (err *InvalidParameterValue) Error() string {
+	return fmt.Sprintf("Invalid value '%s' for parameter '%s'", err.Value, err.Parameter)
+}

src/scanner/queueDirectory.go

@@ -21,15 +21,15 @@ func (s *Scanner) queueDirectory(directory string, pkg string) {
 			return
 		}
 
-		if strings.HasSuffix(name, "_linux.q") && config.TargetOS != "linux" {
+		if strings.HasSuffix(name, "_linux.q") && config.TargetOS != config.Linux {
 			return
 		}
 
-		if strings.HasSuffix(name, "_mac.q") && config.TargetOS != "mac" {
+		if strings.HasSuffix(name, "_mac.q") && config.TargetOS != config.Mac {
 			return
 		}
 
-		if strings.HasSuffix(name, "_windows.q") && config.TargetOS != "windows" {
+		if strings.HasSuffix(name, "_windows.q") && config.TargetOS != config.Windows {
 			return
 		}