add an indentation estimation to printLength

internal/gofumpt.go

@@ -20,9 +20,7 @@ import (
 
 // Multiline nodes which could fit on a single line under this many
 // bytes may be collapsed onto a single line.
-// TODO: Increase this to 60 once we take indentation into account. For now,
-// subtract two tabs.
-const shortLineLimit = 44
+const shortLineLimit = 60
 
 func GofumptBytes(src []byte) ([]byte, error) {
 	fset := token.NewFileSet()
@@ -150,9 +148,21 @@ func (f *fumpter) printLength(node ast.Node) int {
 	if err := format.Node(&count, f.fset, node); err != nil {
 		panic(fmt.Sprintf("unexpected print error: %v", err))
 	}
+
+	// Add the space taken by an inline comment.
 	if c := f.inlineComment(node.End()); c != nil {
 		fmt.Fprintf(&count, " %s", c.Text)
 	}
+
+	// Add an approximation of the indentation level. We can't know the
+	// number of tabs go/printer will add ahead of time. Trying to print the
+	// entire top-level declaration would tell us that, but then it's near
+	// impossible to reliably find our node again.
+	for _, parent := range f.stack {
+		if _, ok := parent.(*ast.BlockStmt); ok {
+			count += 8
+		}
+	}
 	return int(count)
 }
 

testdata/scripts/short-case.txt

@@ -32,6 +32,20 @@ func f(r rune) {
 	case 'a', 'b', 'c',
 		'd': // short comment
 	}
+	{
+		{
+			{
+				{
+					{
+						switch r {
+						case 'i', 'n', 'd', 'e',
+							'n', 't', 'e', 'd':
+						}
+					}
+				}
+			}
+		}
+	}
 }
 -- foo.go.golden --
 package p
@@ -59,4 +73,18 @@ func f(r rune) {
 
 	case 'a', 'b', 'c', 'd': // short comment
 	}
+	{
+		{
+			{
+				{
+					{
+						switch r {
+						case 'i', 'n', 'd', 'e',
+							'n', 't', 'e', 'd':
+						}
+					}
+				}
+			}
+		}
+	}
 }