From aa5fe93f311924d05061c7fa0192c25cc3849058 Mon Sep 17 00:00:00 2001
From: Dmitry Stoletov <irvis@imega.ru>
Date: Tue, 16 Feb 2021 10:48:09 +0300
Subject: [PATCH] add a newline

Before declaration a function or if statement or return statement
if previous statement is not assignment or newline then a newline
will be added before it.

Signed-off-by: Dmitry Stoletov <irvis@imega.ru>
---
 formatter/body.go          | 31 +++++++++++++++++++++++++++----
 formatter/document.go      |  1 +
 formatter/exp.go           |  8 ++------
 formatter/fieldlist.go     |  6 +-----
 formatter/statement_if.go  |  2 +-
 tests/default/0004.lua.fmt |  1 +
 tests/default/0005.lua.fmt |  1 +
 tests/default/0007.lua.fmt |  1 +
 8 files changed, 35 insertions(+), 16 deletions(-)

diff --git a/formatter/body.go b/formatter/body.go
index dcf2760..944e2a6 100644
--- a/formatter/body.go
+++ b/formatter/body.go
@@ -168,10 +168,33 @@ func (b *body) Format(c *Config, p printer, w io.Writer) error {
 }
 
 func isSemanticNewline(prev statement, cur statement) bool {
-	if prev != nil {
-		if cur.TypeOf() == tsReturn && prev.TypeOf() != tsNewline && prev.TypeOf() != tsComment {
-			return true
-		}
+	if prev == nil {
+		return false
+	}
+
+	if prev.TypeOf() == tsNewline || prev.TypeOf() == tsComment {
+		return false
+	}
+
+	if cur.TypeOf() == tsReturn {
+		// always before tsAssignment
+		return true
+	}
+
+	if prev.TypeOf() == tsAssignment {
+		return false
+	}
+
+	if cur.TypeOf() == tsFunction {
+		return true
+	}
+
+	if cur.TypeOf() == tsIfStatement {
+		return true
+	}
+
+	if cur.TypeOf() == tsAssignment {
+		return true
 	}
 
 	return false
diff --git a/formatter/document.go b/formatter/document.go
index 9e7a031..3e559c0 100644
--- a/formatter/document.go
+++ b/formatter/document.go
@@ -48,6 +48,7 @@ const (
 	tsReturn
 	tsNewline
 	tsComment
+	tsIfStatement
 )
 
 // chunk ::= block
diff --git a/formatter/exp.go b/formatter/exp.go
index 43aa872..79e343a 100644
--- a/formatter/exp.go
+++ b/formatter/exp.go
@@ -524,17 +524,13 @@ func (s *exp) Format(c *Config, p printer, w io.Writer) error {
 		}
 
 		if s.Binop.Token.Type == nConcat {
-			curpos, ok := w.(cursorPositioner)
-			if !ok {
-				return nil
-			}
-
 			buf := bytes.NewBuffer(nil)
 			if err := s.Exp.Format(c, p, buf); err != nil {
 				return err
 			}
 
-			if curpos.Cursor().Col+uint64(buf.Len()) > uint64(c.MaxLineLength) {
+			curpos := getCursorPosition(w)
+			if curpos.Col+uint64(buf.Len()) > uint64(c.MaxLineLength) {
 				if err := newLine(w); err != nil {
 					return err
 				}
diff --git a/formatter/fieldlist.go b/formatter/fieldlist.go
index f6562b6..c2d9fea 100644
--- a/formatter/fieldlist.go
+++ b/formatter/fieldlist.go
@@ -193,11 +193,7 @@ type fieldLength struct {
 }
 
 func (s *fieldlist) isInline(c *Config, p printer, w io.Writer) bool {
-	var curpos cursorPosition
-
-	if v, ok := w.(cursorPositioner); ok {
-		curpos = v.Cursor()
-	}
+	curpos := getCursorPosition(w)
 
 	buf := bytes.NewBuffer([]byte("{}"))
 
diff --git a/formatter/statement_if.go b/formatter/statement_if.go
index 28b45f4..0859f72 100644
--- a/formatter/statement_if.go
+++ b/formatter/statement_if.go
@@ -31,7 +31,7 @@ func (ifStatement) InnerStatement(prev, cur *element) (bool, statement) {
 }
 
 func (ifStatement) TypeOf() typeStatement {
-	return tsNone
+	return tsIfStatement
 }
 
 func (s *ifStatement) IsEnd(prev, cur *element) (bool, bool) {
diff --git a/tests/default/0004.lua.fmt b/tests/default/0004.lua.fmt
index c88eede..c80db0d 100644
--- a/tests/default/0004.lua.fmt
+++ b/tests/default/0004.lua.fmt
@@ -17,5 +17,6 @@ else
         return 4
     end
 end
+
 c = b()
 print(c)
diff --git a/tests/default/0005.lua.fmt b/tests/default/0005.lua.fmt
index d2eee8c..1dfa00d 100644
--- a/tests/default/0005.lua.fmt
+++ b/tests/default/0005.lua.fmt
@@ -97,6 +97,7 @@ local vehicles = load_vehicles_from_disk("vehicles.dat")
 
 if vehicles["Porsche"] then
     porsche_handler(vehicles["Porsche"])
+
     vehicles["Porsche"] = nil
 end
 
diff --git a/tests/default/0007.lua.fmt b/tests/default/0007.lua.fmt
index 224051d..1e48c23 100644
--- a/tests/default/0007.lua.fmt
+++ b/tests/default/0007.lua.fmt
@@ -34,6 +34,7 @@ end
 local function foo()
     -- code
 end
+
 local function bar()
     -- code
 end