Improved error handling

src/build/Function.go

@@ -7,14 +7,16 @@ import (
 	"git.akyoto.dev/cli/q/src/build/arch/x64"
 	"git.akyoto.dev/cli/q/src/build/asm"
 	"git.akyoto.dev/cli/q/src/build/config"
+	"git.akyoto.dev/cli/q/src/build/fs"
 	"git.akyoto.dev/cli/q/src/build/token"
+	"git.akyoto.dev/cli/q/src/errors"
 	"git.akyoto.dev/go/color/ansi"
 )
 
 // Function represents a function.
 type Function struct {
 	Name      string
-	File      *File
+	File      *fs.File
 	Head      token.List
 	Body      token.List
 	Variables map[string]*Variable
@@ -74,6 +76,12 @@ func (f *Function) Compile() {
 	f.Assembler.Return()
 
 	if config.Verbose {
+		f.PrintAsm()
+	}
+}
+
+// PrintAsm shows the assembly instructions.
+func (f *Function) PrintAsm() {
 	fmt.Println()
 	ansi.Bold.Println(f.Name + ".asm")
 
@@ -88,7 +96,6 @@ func (f *Function) Compile() {
 		fmt.Print("\n")
 	}
 }
-}
 
 // CompileInstruction compiles a single instruction.
 func (f *Function) CompileInstruction(line token.List) error {
@@ -116,8 +123,7 @@ func (f *Function) CompileInstruction(line token.List) error {
 			value := line[2:]
 
 			if len(value) == 0 {
-				return fmt.Errorf("error to be implemented")
+				return errors.New(errors.MissingAssignmentValue, f.File, line[1].After())
-				// return errors.New(errors.MissingAssignmentValue, f.File.Path, f.File.Tokens, f.Cursor)
 			}
 
 			if config.Verbose {

src/build/Scan.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"sync"
 
-	"git.akyoto.dev/cli/q/src/build/directory"
+	"git.akyoto.dev/cli/q/src/build/fs"
 	"git.akyoto.dev/cli/q/src/build/token"
 	"git.akyoto.dev/cli/q/src/errors"
 )
@@ -38,7 +38,7 @@ func scan(files []string, functions chan<- *Function, errors chan<- error) {
 		}
 
 		if stat.IsDir() {
-			err = directory.Walk(file, func(name string) {
+			err = fs.Walk(file, func(name string) {
 				if !strings.HasSuffix(name, ".q") {
 					return
 				}
@@ -86,7 +86,7 @@ func scanFile(path string, functions chan<- *Function) error {
 
 	tokens := token.Tokenize(contents)
 
-	file := &File{
+	file := &fs.File{
 		Tokens: tokens,
 		Path:   path,
 	}
@@ -118,7 +118,7 @@ func scanFile(path string, functions chan<- *Function) error {
 				return nil
 			}
 
-			return errors.New(errors.ExpectedFunctionName, path, tokens, i)
+			return errors.New(errors.ExpectedFunctionName, file, tokens[i].Position)
 		}
 
 		// Function parameters
@@ -138,7 +138,7 @@ func scanFile(path string, functions chan<- *Function) error {
 				groupLevel--
 
 				if groupLevel < 0 {
-					return errors.New(errors.MissingGroupStart, path, tokens, i)
+					return errors.New(errors.MissingGroupStart, file, tokens[i].Position)
 				}
 
 				i++
@@ -152,11 +152,11 @@ func scanFile(path string, functions chan<- *Function) error {
 
 			if tokens[i].Kind == token.EOF {
 				if groupLevel > 0 {
-					return errors.New(errors.MissingGroupEnd, path, tokens, i)
+					return errors.New(errors.MissingGroupEnd, file, tokens[i].Position)
 				}
 
 				if paramsStart == -1 {
-					return errors.New(errors.ExpectedFunctionParameters, path, tokens, i)
+					return errors.New(errors.ExpectedFunctionParameters, file, tokens[i].Position)
 				}
 
 				return nil
@@ -167,7 +167,7 @@ func scanFile(path string, functions chan<- *Function) error {
 				continue
 			}
 
-			return errors.New(errors.ExpectedFunctionParameters, path, tokens, i)
+			return errors.New(errors.ExpectedFunctionParameters, file, tokens[i].Position)
 		}
 
 		// Function definition
@@ -187,7 +187,7 @@ func scanFile(path string, functions chan<- *Function) error {
 				blockLevel--
 
 				if blockLevel < 0 {
-					return errors.New(errors.MissingBlockStart, path, tokens, i)
+					return errors.New(errors.MissingBlockStart, file, tokens[i].Position)
 				}
 
 				i++
@@ -201,11 +201,11 @@ func scanFile(path string, functions chan<- *Function) error {
 
 			if tokens[i].Kind == token.EOF {
 				if blockLevel > 0 {
-					return errors.New(errors.MissingBlockEnd, path, tokens, i)
+					return errors.New(errors.MissingBlockEnd, file, tokens[i].Position)
 				}
 
 				if bodyStart == -1 {
-					return errors.New(errors.ExpectedFunctionDefinition, path, tokens, i)
+					return errors.New(errors.ExpectedFunctionDefinition, file, tokens[i].Position)
 				}
 
 				return nil
@@ -216,7 +216,7 @@ func scanFile(path string, functions chan<- *Function) error {
 				continue
 			}
 
-			return errors.New(errors.ExpectedFunctionDefinition, path, tokens, i)
+			return errors.New(errors.ExpectedFunctionDefinition, file, tokens[i].Position)
 		}
 
 		functions <- &Function{

src/build/fs/File.go

@@ -1,4 +1,4 @@
-package build
+package fs
 
 import "git.akyoto.dev/cli/q/src/build/token"
 

src/build/fs/Walk.go

@@ -1,4 +1,4 @@
-package directory
+package fs
 
 import (
 	"syscall"

src/build/fs/Walk_test.go

@@ -1,16 +1,16 @@
-package directory_test
+package fs_test
 
 import (
 	"testing"
 
-	"git.akyoto.dev/cli/q/src/build/directory"
+	"git.akyoto.dev/cli/q/src/build/fs"
 	"git.akyoto.dev/go/assert"
 )
 
 func TestWalk(t *testing.T) {
 	var files []string
 
-	directory.Walk(".", func(file string) {
+	fs.Walk(".", func(file string) {
 		files = append(files, file)
 	})
 
@@ -19,6 +19,6 @@ func TestWalk(t *testing.T) {
 }
 
 func TestNonExisting(t *testing.T) {
-	err := directory.Walk("does-not-exist", func(file string) {})
+	err := fs.Walk("does-not-exist", func(file string) {})
 	assert.NotNil(t, err)
 }

src/build/token/Token.go

@@ -11,6 +11,11 @@ type Token struct {
 	Bytes    []byte
 }
 
+// After returns the position after the token.
+func (t Token) After() int {
+	return t.Position + len(t.Bytes)
+}
+
 // String creates a human readable representation for debugging purposes.
 func (t Token) String() string {
 	return fmt.Sprintf("%s %s", t.Kind, t.Text())

src/errors/Error.go

@@ -5,60 +5,60 @@ import (
 	"os"
 	"path/filepath"
 
+	"git.akyoto.dev/cli/q/src/build/fs"
 	"git.akyoto.dev/cli/q/src/build/token"
 )
 
 // Error is a compiler error at a given line and column.
 type Error struct {
-	Path   string
-	Line   int
-	Column int
 	Err      error
+	File     *fs.File
+	Position int
 	Stack    string
 }
 
 // New generates an error message at the current token position.
 // The error message is clickable in popular editors and leads you
 // directly to the faulty file at the given line and position.
-func New(err error, path string, tokens []token.Token, cursor int) *Error {
+func New(err error, file *fs.File, position int) *Error {
-	var (
+	return &Error{
-		lineCount = 1
+		Err:      err,
-		lineStart = -1
+		File:     file,
-	)
+		Position: position,
-
+		Stack:    Stack(),
-	for i := range cursor {
-		if tokens[i].Kind == token.NewLine {
-			lineCount++
-			lineStart = int(tokens[i].Position)
 	}
 }
 
-	var column int
-
-	if cursor < len(tokens) {
-		column = tokens[cursor].Position - lineStart
-	} else {
-		lastToken := tokens[len(tokens)-1]
-		column = lastToken.Position - lineStart + len(lastToken.Text())
-	}
-
-	return &Error{path, lineCount, column, err, Stack()}
-}
-
 // Error generates the string representation.
 func (e *Error) Error() string {
-	path := e.Path
+	path := e.File.Path
 	cwd, err := os.Getwd()
 
 	if err == nil {
-		relativePath, err := filepath.Rel(cwd, e.Path)
+		relativePath, err := filepath.Rel(cwd, e.File.Path)
 
 		if err == nil {
 			path = relativePath
 		}
 	}
 
-	return fmt.Sprintf("%s:%d:%d: %s\n\n%s", path, e.Line, e.Column, e.Err, e.Stack)
+	line := 1
+	column := 1
+	lineStart := -1
+
+	for _, t := range e.File.Tokens {
+		if t.Position >= e.Position {
+			column = e.Position - lineStart
+			break
+		}
+
+		if t.Kind == token.NewLine {
+			lineStart = t.Position
+			line++
+		}
+	}
+
+	return fmt.Sprintf("%s:%d:%d: %s\n\n%s", path, line, column, e.Err, e.Stack)
 }
 
 // Unwrap returns the wrapped error.