caddyfile: Fix comparing if two tokens are on the same line (#5626)

* fix comparing if two tokens are on the same line

* compare tokens from copies when importing

3 files changed, 30 insertions, 25 deletions

diff --git a/caddyconfig/caddyfile/dispenser.go b/caddyconfig/caddyfile/dispenser.go
index 580de4a9b..6c33f4fe6 100644
--- a/caddyconfig/caddyfile/dispenser.go
+++ b/caddyconfig/caddyfile/dispenser.go
@@ -106,7 +106,7 @@ func (d *Dispenser) nextOnSameLine() bool {
 	}
 	curr := d.tokens[d.cursor]
 	next := d.tokens[d.cursor+1]
-	if curr.File == next.File && curr.Line+curr.NumLineBreaks() == next.Line {
+	if !isNextOnNewLine(curr, next) {
 		d.cursor++
 		return true
 	}
@@ -127,7 +127,7 @@ func (d *Dispenser) NextLine() bool {
 	}
 	curr := d.tokens[d.cursor]
 	next := d.tokens[d.cursor+1]
-	if curr.File != next.File || curr.Line+curr.NumLineBreaks() < next.Line {
+	if isNextOnNewLine(curr, next) {
 		d.cursor++
 		return true
 	}
@@ -464,17 +464,7 @@ func (d *Dispenser) isNewLine() bool {
 
 	prev := d.tokens[d.cursor-1]
 	curr := d.tokens[d.cursor]
-
-	// If the previous token is from a different file,
-	// we can assume it's from a different line
-	if prev.File != curr.File {
-		return true
-	}
-
-	// If the previous token (incl line breaks) ends
-	// on a line earlier than the current token,
-	// then the current token is on a new line
-	return prev.Line+prev.NumLineBreaks() < curr.Line
+	return isNextOnNewLine(prev, curr)
 }
 
 // isNextOnNewLine determines whether the current token is on a different
@@ -490,15 +480,5 @@ func (d *Dispenser) isNextOnNewLine() bool {
 
 	curr := d.tokens[d.cursor]
 	next := d.tokens[d.cursor+1]
-
-	// If the next token is from a different file,
-	// we can assume it's from a different line
-	if curr.File != next.File {
-		return true
-	}
-
-	// If the current token (incl line breaks) ends
-	// on a line earlier than the next token,
-	// then the next token is on a new line
-	return curr.Line+curr.NumLineBreaks() < next.Line
+	return isNextOnNewLine(curr, next)
 }
diff --git a/caddyconfig/caddyfile/lexer.go b/caddyconfig/caddyfile/lexer.go
index d1fbfbb42..47aaa0314 100644
--- a/caddyconfig/caddyfile/lexer.go
+++ b/caddyconfig/caddyfile/lexer.go
@@ -338,3 +338,28 @@ func (t Token) NumLineBreaks() int {
 }
 
 var heredocMarkerRegexp = regexp.MustCompile("^[A-Za-z0-9_-]+$")
+
+// isNextOnNewLine tests whether t2 is on a different line from t1
+func isNextOnNewLine(t1, t2 Token) bool {
+	// If the second token is from a different file,
+	// we can assume it's from a different line
+	if t1.File != t2.File {
+		return true
+	}
+
+	// If the second token is from a different import chain,
+	// we can assume it's from a different line
+	if len(t1.imports) != len(t2.imports) {
+		return true
+	}
+	for i, im := range t1.imports {
+		if im != t2.imports[i] {
+			return true
+		}
+	}
+
+	// If the first token (incl line breaks) ends
+	// on a line earlier than the next token,
+	// then the second token is on a new line
+	return t1.Line+t1.NumLineBreaks() < t2.Line
+}
diff --git a/caddyconfig/caddyfile/parse.go b/caddyconfig/caddyfile/parse.go
index 81181a473..0a1a9e7b1 100644
--- a/caddyconfig/caddyfile/parse.go
+++ b/caddyconfig/caddyfile/parse.go
@@ -464,7 +464,7 @@ func (p *parser) doImport(nesting int) error {
 		// format, won't check for nesting correctness or any other error, that's what parser does.
 		if !maybeSnippet && nesting == 0 {
 			// first of the line
-			if i == 0 || importedTokens[i-1].File != token.File || importedTokens[i-1].Line+importedTokens[i-1].NumLineBreaks() < token.Line {
+			if i == 0 || isNextOnNewLine(tokensCopy[i-1], token) {
 				index = 0
 			} else {
 				index++