more fixes to docstring and comments in general

Author: MerlinVeritas

internal/printer/printer.go

@@ -37,6 +37,22 @@ func (w *writer) printIndent(indent int32) {
 	}
 }
 
+func (w *writer) printCommentText(text string, indent int32) {
+	lines := strings.Split(text, "\n")
+	for _, line := range lines {
+		w.print("#")
+		// trim right space which is usually unintended,
+		// but leave left space untouched in case if it's intentionally formatted.
+		trimmed := strings.TrimRight(line, " ")
+		if trimmed != "" {
+			w.print(" ")
+			w.print(trimmed)
+		}
+		w.print("\n")
+		w.printIndent(indent)
+	}
+}
+
 func (w *writer) printNode(node *ast.Node, indent int32) {
 	switch n := node.Node.(type) {
 
@@ -132,10 +148,7 @@ func (w *writer) printNode(node *ast.Node, indent int32) {
 
 func (w *writer) printAnnAssign(aa *ast.AnnAssign, indent int32) {
 	if aa.Comment != "" {
-		w.print("# ")
-		w.print(aa.Comment)
-		w.print("\n")
-		w.printIndent(indent)
+		w.printCommentText(aa.Comment, indent)
 	}
 	w.printName(aa.Target, indent)
 	w.print(": ")
@@ -255,10 +268,7 @@ func (w *writer) printClassDef(cd *ast.ClassDef, indent int32) {
 		if i == 0 {
 			if e, ok := node.Node.(*ast.Node_Expr); ok {
 				if c, ok := e.Expr.Value.Node.(*ast.Node_Constant); ok {
-					w.print(`""`)
-					w.printConstant(c.Constant, indent)
-					w.print(`""`)
-					w.print("\n")
+					w.printDocString(c.Constant, indent)
 					continue
 				}
 			}
@@ -268,6 +278,33 @@ func (w *writer) printClassDef(cd *ast.ClassDef, indent int32) {
 	}
 }
 
+func (w *writer) printDocString(c *ast.Constant, indent int32) {
+	switch n := c.Value.(type) {
+	case *ast.Constant_Str:
+		w.print(`"""`)
+		lines := strings.Split(n.Str, "\n")
+		printedN := 0
+		for n, line := range lines {
+			// trim right space which is usually unintended,
+			// but leave left space untouched in case if it's intentionally formatted.
+			trimmed := strings.TrimRight(line, " ")
+			if trimmed == "" {
+				continue
+			}
+			if printedN > 0 && n < len(lines)-1 {
+				w.print("\n")
+				w.printIndent(indent)
+			}
+			w.print(strings.ReplaceAll(trimmed, `"`, `\"`))
+			printedN++
+		}
+		w.print(`"""`)
+		w.print("\n")
+	default:
+		panic(n)
+	}
+}
+
 func (w *writer) printConstant(c *ast.Constant, indent int32) {
 	switch n := c.Value.(type) {
 	case *ast.Constant_Int:
@@ -291,9 +328,7 @@ func (w *writer) printConstant(c *ast.Constant, indent int32) {
 }
 
 func (w *writer) printComment(c *ast.Comment, indent int32) {
-	w.print("# ")
-	w.print(c.Text)
-	w.print("\n")
+	w.printCommentText(c.Text, 0)
 }
 
 func (w *writer) printCompare(c *ast.Compare, indent int32) {