Add support for extendedDiagnostics json output

cmd/tsgo/diagnostics.go

@@ -0,0 +1,107 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// max returns the larger of x or y
+func max(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}
+
+// tableRow represents a single row in the diagnostic table
+type tableRow struct {
+	name  string
+	value string
+}
+
+// table collects and formats diagnostic data
+type table struct {
+	rows []tableRow
+}
+
+// add adds a statistic to the table, automatically formatting durations
+func (t *table) add(name string, value any) {
+	if d, ok := value.(time.Duration); ok {
+		value = formatDuration(d)
+	}
+	t.rows = append(t.rows, tableRow{name, fmt.Sprint(value)})
+}
+
+// toJSON converts the table to a map suitable for JSON serialization
+func (t *table) toJSON() map[string]string {
+	result := make(map[string]string)
+	for _, row := range t.rows {
+		result[row.name] = row.value
+	}
+	return result
+}
+
+// print outputs the table in a formatted way to stdout
+func (t *table) print() {
+	nameWidth := 0
+	valueWidth := 0
+	for _, r := range t.rows {
+		nameWidth = max(nameWidth, len(r.name))
+		valueWidth = max(valueWidth, len(r.value))
+	}
+
+	for _, r := range t.rows {
+		fmt.Printf("%-*s %*s\n", nameWidth+1, r.name+":", valueWidth, r.value)
+	}
+}
+
+// formatDuration formats a duration in seconds with 3 decimal places
+func formatDuration(d time.Duration) string {
+	return fmt.Sprintf("%.3fs", d.Seconds())
+}
+
+// OutputStats handles the output of diagnostic statistics based on the extendedDiagnostics option
+// Returns any error encountered during the output process
+func OutputStats(stats *table, extendedDiagnostics string) error {
+
+	if extendedDiagnostics == "" {
+		return nil
+	}
+
+	if extendedDiagnostics == "inline" {
+		stats.print()
+		return nil
+	}
+
+	jsonData := stats.toJSON()
+
+	if strings.HasSuffix(extendedDiagnostics, ".json") {
+		// Ensure directory exists
+		dir := filepath.Dir(extendedDiagnostics)
+		if dir != "." {
+			if err := os.MkdirAll(dir, 0755); err != nil {
+				return fmt.Errorf("error creating directory for stats JSON file: %w", err)
+			}
+		}
+
+		// Write to file
+		file, err := os.Create(extendedDiagnostics)
+		if err != nil {
+			return fmt.Errorf("error creating stats JSON file: %w", err)
+		}
+		defer file.Close()
+
+		enc := json.NewEncoder(file)
+		enc.SetIndent("", "  ")
+		if err := enc.Encode(jsonData); err != nil {
+			return fmt.Errorf("error writing stats to JSON file: %w", err)
+		}
+		return nil
+	}
+
+	return fmt.Errorf("invalid value for --extendedDiagnostics. Use 'inline' or a path ending with '.json'")
+}

cmd/tsgo/main.go

@@ -64,10 +64,11 @@ type cliOptions struct {
 	}
 
 	devel struct {
-		quiet          bool
-		singleThreaded bool
-		printTypes     bool
-		pprofDir       string
+		quiet               bool
+		singleThreaded      bool
+		printTypes          bool
+		pprofDir            string
+		extendedDiagnostics string
 	}
 }
 
@@ -112,6 +113,7 @@ func parseArgs() *cliOptions {
 	flag.BoolVar(&opts.devel.singleThreaded, "singleThreaded", false, "Run in single threaded mode.")
 	flag.BoolVar(&opts.devel.printTypes, "printTypes", false, "Print types defined in 'main.ts'.")
 	flag.StringVar(&opts.devel.pprofDir, "pprofDir", "", "Generate pprof CPU/memory profiles to the given directory.")
+	flag.StringVar(&opts.devel.extendedDiagnostics, "extendedDiagnostics", "", "Output extended diagnostics. Use 'inline' for stdout text output or a '.json' file path to write to a file.")
 	flag.Parse()
 
 	if len(flag.Args()) > 0 {
@@ -295,42 +297,11 @@ func runMain() int {
 	}
 	stats.add("Total time", totalTime)
 
-	stats.print()
-
-	return exitCode
-}
-
-type tableRow struct {
-	name  string
-	value string
-}
-
-type table struct {
-	rows []tableRow
-}
-
-func (t *table) add(name string, value any) {
-	if d, ok := value.(time.Duration); ok {
-		value = formatDuration(d)
-	}
-	t.rows = append(t.rows, tableRow{name, fmt.Sprint(value)})
-}
-
-func (t *table) print() {
-	nameWidth := 0
-	valueWidth := 0
-	for _, r := range t.rows {
-		nameWidth = max(nameWidth, len(r.name))
-		valueWidth = max(valueWidth, len(r.value))
+	if err := OutputStats(&stats, opts.devel.extendedDiagnostics); err != nil {
+		fmt.Fprintf(os.Stderr, "%v\n", err)
 	}
 
-	for _, r := range t.rows {
-		fmt.Printf("%-*s %*s\n", nameWidth+1, r.name+":", valueWidth, r.value)
-	}
-}
-
-func formatDuration(d time.Duration) string {
-	return fmt.Sprintf("%.3fs", d.Seconds())
+	return exitCode
 }
 
 func identifierCount(p *compiler.Program) int {