From e652f815efc5972fdb86f43be7618aaa925be3e7 Mon Sep 17 00:00:00 2001
From: cvgw <cgwippern@google.com>
Date: Mon, 20 Jan 2020 15:57:05 -0800
Subject: [PATCH] Fix #519 capital letter in stage names

update stage code so that when comparing the BaseName of
a stage against the recorded, lowercase version of a Stage name
the BaseName is also lowercased.
---
 .../Dockerfile_test_from_multistage_capital         | 13 +++++++++++++
 pkg/dockerfile/dockerfile.go                        | 11 +++++++++--
 2 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 integration/dockerfiles/Dockerfile_test_from_multistage_capital

diff --git a/integration/dockerfiles/Dockerfile_test_from_multistage_capital b/integration/dockerfiles/Dockerfile_test_from_multistage_capital
new file mode 100644
index 000000000..7bba24ad1
--- /dev/null
+++ b/integration/dockerfiles/Dockerfile_test_from_multistage_capital
@@ -0,0 +1,13 @@
+FROM alpine as base_stage
+
+RUN echo base_stage
+
+
+FROM base_stage as BUG_stage
+
+RUN echo BUG_stage
+
+
+FROM BUG_stage as final_stage
+
+RUN echo final_stage
diff --git a/pkg/dockerfile/dockerfile.go b/pkg/dockerfile/dockerfile.go
index 1f1314fb4..f41875c56 100644
--- a/pkg/dockerfile/dockerfile.go
+++ b/pkg/dockerfile/dockerfile.go
@@ -90,14 +90,17 @@ func Stages(opts *config.KanikoOptions) ([]config.KanikoStage, error) {
 // baseImageIndex returns the index of the stage the current stage is built off
 // returns -1 if the current stage isn't built off a previous stage
 func baseImageIndex(currentStage int, stages []instructions.Stage) int {
+	currentStageBaseName := strings.ToLower(stages[currentStage].BaseName)
+
 	for i, stage := range stages {
 		if i > currentStage {
 			break
 		}
-		if stage.Name == stages[currentStage].BaseName {
+		if stage.Name == currentStageBaseName {
 			return i
 		}
 	}
+
 	return -1
 }
 
@@ -245,15 +248,19 @@ func ParseCommands(cmdArray []string) ([]instructions.Command, error) {
 
 // SaveStage returns true if the current stage will be needed later in the Dockerfile
 func saveStage(index int, stages []instructions.Stage) bool {
+	currentStageName := stages[index].Name
+
 	for stageIndex, stage := range stages {
 		if stageIndex <= index {
 			continue
 		}
-		if stage.BaseName == stages[index].Name {
+
+		if strings.ToLower(stage.BaseName) == currentStageName {
 			if stage.BaseName != "" {
 				return true
 			}
 		}
 	}
+
 	return false
 }