From 9661aaa830fd00df65d3bf64cfe25cfd56f35024 Mon Sep 17 00:00:00 2001
From: Shahms King <shahms@google.com>
Date: Wed, 22 May 2019 10:02:47 -0700
Subject: [PATCH] support Python multi-line values with empty first line

---
 ini_test.go |  5 +++++
 parser.go   | 59 ++++++++++++++++++++++++++++++-----------------------
 2 files changed, 38 insertions(+), 26 deletions(-)

diff --git a/ini_test.go b/ini_test.go
index 767b461..7193823 100644
--- a/ini_test.go
+++ b/ini_test.go
@@ -507,11 +507,16 @@ long_rsa_private_key = -----BEGIN RSA PRIVATE KEY-----
   foobar
   barfoo
   -----END RSA PRIVATE KEY-----
+multiline_list =
+  first
+  second
+  third
 `))
 				So(err, ShouldBeNil)
 				So(f, ShouldNotBeNil)
 
 				So(f.Section("long").Key("long_rsa_private_key").String(), ShouldEqual, "-----BEGIN RSA PRIVATE KEY-----\nfoo\nbar\nfoobar\nbarfoo\n-----END RSA PRIVATE KEY-----")
+				So(f.Section("long").Key("multiline_list").String(), ShouldEqual, "\nfirst\nsecond\nthird")
 			})
 
 			Convey("Can parse big python-compatible INI files", func() {
diff --git a/parser.go b/parser.go
index a869651..4a95b55 100644
--- a/parser.go
+++ b/parser.go
@@ -204,6 +204,9 @@ func (p *parser) readValue(in []byte, bufferSize int) (string, error) {
 
 	line := strings.TrimLeftFunc(string(in), unicode.IsSpace)
 	if len(line) == 0 {
+		if p.options.AllowPythonMultilineValues && len(in) > 0 && in[len(in)-1] == '\n' {
+			return p.readPythonMultilines(line, bufferSize)
+		}
 		return "", nil
 	}
 
@@ -272,42 +275,46 @@ func (p *parser) readValue(in []byte, bufferSize int) (string, error) {
 			line = strings.Replace(line, `\#`, "#", -1)
 		}
 	} else if p.options.AllowPythonMultilineValues && lastChar == '\n' {
-		parserBufferPeekResult, _ := p.buf.Peek(bufferSize)
-		peekBuffer := bytes.NewBuffer(parserBufferPeekResult)
+		return p.readPythonMultilines(line, bufferSize)
+	}
 
-		val := line
+	return line, nil
+}
 
-		for {
-			peekData, peekErr := peekBuffer.ReadBytes('\n')
-			if peekErr != nil {
-				if peekErr == io.EOF {
-					return val, nil
-				}
-				return "", peekErr
-			}
+func (p *parser) readPythonMultilines(line string, bufferSize int) (string, error) {
+	parserBufferPeekResult, _ := p.buf.Peek(bufferSize)
+	peekBuffer := bytes.NewBuffer(parserBufferPeekResult)
 
-			peekMatches := pythonMultiline.FindStringSubmatch(string(peekData))
-			if len(peekMatches) != 3 {
-				return val, nil
-			}
+	val := line
 
-			// NOTE: Return if not a python-ini multi-line value.
-			currentIdentSize := len(peekMatches[1])
-			if currentIdentSize <= 0 {
+	for {
+		peekData, peekErr := peekBuffer.ReadBytes('\n')
+		if peekErr != nil {
+			if peekErr == io.EOF {
 				return val, nil
 			}
+			return "", peekErr
+		}
 
-			// NOTE: Just advance the parser reader (buffer) in-sync with the peek buffer.
-			_, err := p.readUntil('\n')
-			if err != nil {
-				return "", err
-			}
+		peekMatches := pythonMultiline.FindStringSubmatch(string(peekData))
+		if len(peekMatches) != 3 {
+			return val, nil
+		}
 
-			val += fmt.Sprintf("\n%s", peekMatches[2])
+		// NOTE: Return if not a python-ini multi-line value.
+		currentIdentSize := len(peekMatches[1])
+		if currentIdentSize <= 0 {
+			return val, nil
 		}
-	}
 
-	return line, nil
+		// NOTE: Just advance the parser reader (buffer) in-sync with the peek buffer.
+		_, err := p.readUntil('\n')
+		if err != nil {
+			return "", err
+		}
+
+		val += fmt.Sprintf("\n%s", peekMatches[2])
+	}
 }
 
 // parse parses data through an io.Reader.