feat: publish the Sandwich Hime source preview

Signed-off-by: Cole Speelman <gamertan@noreply.localhost>

internal/compiler/diagnostic.go

@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: AGPL-3.0-only
+
+// Package compiler implements the Hime-san .sando compiler.
+package compiler
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// Severity describes the impact of a diagnostic.
+type Severity string
+
+const (
+	SeverityError   Severity = "error"
+	SeverityWarning Severity = "warning"
+)
+
+// Diagnostic is a stable, machine-readable compiler message. Line and Column
+// are one-based. A diagnostic without a source position uses line and column 1.
+type Diagnostic struct {
+	Path     string   `json:"path"`
+	Line     int      `json:"line"`
+	Column   int      `json:"column"`
+	Code     string   `json:"code"`
+	Severity Severity `json:"severity"`
+	Message  string   `json:"message"`
+}
+
+func (d Diagnostic) Error() string {
+	line, column := d.Line, d.Column
+	if line < 1 {
+		line = 1
+	}
+	if column < 1 {
+		column = 1
+	}
+	return fmt.Sprintf("%s:%d:%d: %s: %s", d.Path, line, column, d.Code, d.Message)
+}
+
+// DiagnosticsError reports one or more error diagnostics.
+type DiagnosticsError struct {
+	Diagnostics []Diagnostic
+}
+
+func (e *DiagnosticsError) Error() string {
+	if e == nil || len(e.Diagnostics) == 0 {
+		return "himesan: compilation failed"
+	}
+	if len(e.Diagnostics) == 1 {
+		return e.Diagnostics[0].Error()
+	}
+	return fmt.Sprintf("%s (and %d more diagnostics)", e.Diagnostics[0].Error(), len(e.Diagnostics)-1)
+}
+
+func errorFromDiagnostics(ds []Diagnostic) error {
+	if !hasErrors(ds) {
+		return nil
+	}
+	copyOfDiagnostics := append([]Diagnostic(nil), ds...)
+	sortDiagnostics(copyOfDiagnostics)
+	return &DiagnosticsError{Diagnostics: copyOfDiagnostics}
+}
+
+func hasErrors(ds []Diagnostic) bool {
+	for _, d := range ds {
+		if d.Severity == SeverityError || d.Severity == "" {
+			return true
+		}
+	}
+	return false
+}
+
+func sortDiagnostics(ds []Diagnostic) {
+	sort.SliceStable(ds, func(i, j int) bool {
+		a, b := ds[i], ds[j]
+		if a.Path != b.Path {
+			return a.Path < b.Path
+		}
+		if a.Line != b.Line {
+			return a.Line < b.Line
+		}
+		if a.Column != b.Column {
+			return a.Column < b.Column
+		}
+		if a.Code != b.Code {
+			return a.Code < b.Code
+		}
+		return a.Message < b.Message
+	})
+}
+
+func diagnostic(path string, pos sourcePosition, code, message string) Diagnostic {
+	return Diagnostic{
+		Path:     path,
+		Line:     pos.Line,
+		Column:   pos.Column,
+		Code:     code,
+		Severity: SeverityError,
+		Message:  strings.TrimSpace(message),
+	}
+}