Add SplitStatements

statement.go

@@ -0,0 +1,134 @@
+package sqluct
+
+import "strings"
+
+// SplitStatements splits a string in multiple SQL statements separated by semicolon (';').
+//
+// Semicolons in comments and string literals are not treated as separators.
+func SplitStatements(s string) []string { //nolint:gocognit,gocyclo,funlen
+	var (
+		quoteChars  = [...]int32{'"', '\'', '`'}
+		quoteOpened int32
+	)
+
+	prevStart := 0
+	prevQuot := false
+
+	// -- Line comment.
+	lineCommentStarted := false
+	prevDash := false
+
+	// /* Block comment */
+	blockCommentStarted := false
+	prevSlash := false
+	prevAsterisk := false
+
+	var res []string
+
+	for i, c := range s {
+		if blockCommentStarted && c != '*' && c != '/' {
+			continue
+		}
+
+		if lineCommentStarted {
+			if c == '\n' {
+				lineCommentStarted = false
+
+				continue
+			}
+
+			continue
+		}
+
+		if quoteOpened != 0 {
+			// This may be a closing quote or an escaped quot if it is immediately followed by another same quot.
+			if c == quoteOpened {
+				if prevQuot {
+					prevQuot = false
+
+					continue
+				}
+
+				prevQuot = true
+
+				continue
+			}
+
+			if prevQuot {
+				prevQuot = false
+				quoteOpened = 0
+			}
+		}
+
+		// quoteOpened is 0
+		for _, q := range quoteChars {
+			if c == q {
+				quoteOpened = q
+			}
+		}
+
+		if quoteOpened != 0 {
+			continue
+		}
+
+		// Might be a line comment.
+		if c == '-' {
+			if prevDash {
+				prevDash = false
+				lineCommentStarted = true
+
+				continue
+			}
+
+			prevDash = true
+		} else {
+			prevDash = false
+		}
+
+		if c == '/' {
+			if prevAsterisk && blockCommentStarted {
+				blockCommentStarted = false
+				prevAsterisk = false
+
+				continue
+			}
+
+			prevSlash = true
+
+			continue
+		}
+
+		if c == '*' {
+			if prevSlash && !blockCommentStarted {
+				blockCommentStarted = true
+				prevSlash = false
+
+				continue
+			}
+
+			prevAsterisk = true
+
+			continue
+		}
+
+		prevSlash = false
+		prevAsterisk = false
+
+		// Not in an enquoted string, so that's a statement separator.
+		if c == ';' {
+			st := strings.TrimSpace(s[prevStart:i])
+			if len(st) > 0 {
+				res = append(res, st)
+			}
+
+			prevStart = i + 1
+		}
+	}
+
+	st := strings.TrimSpace(s[prevStart:])
+	if len(st) > 0 {
+		res = append(res, st)
+	}
+
+	return res
+}

statement_test.go

@@ -0,0 +1,36 @@
+package sqluct_test
+
+import (
+	"testing"
+
+	"github.com/bool64/sqluct"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSplitStatements(t *testing.T) {
+	s := `SELECT "ol'o""lo","",'';
+	-- next sta;tement
+	SELECT * FROM refers order by ts desc limit 15;
+	-- next statement
+	SELECT * FROM visitor WHERE hash=8361038239347337526;
+SELECT /* 1;2;3 */ 'aaa' 
+`
+
+	res := sqluct.SplitStatements(s)
+	assert.Equal(t, []string{
+		`SELECT "ol'o""lo","",''`,
+		"-- next sta;tement\n\tSELECT * FROM refers order by ts desc limit 15",
+		"-- next statement\n\tSELECT * FROM visitor WHERE hash=8361038239347337526",
+		"SELECT /* 1;2;3 */ 'aaa'",
+	}, res)
+}
+
+func TestSplitStatements2(t *testing.T) {
+	s := `";";';'`
+	res := sqluct.SplitStatements(s)
+
+	assert.Equal(t, []string{
+		`";"`,
+		`';'`,
+	}, res)
+}