From fef0b9d6274043dcc7b62c475973696b5a108c0e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Magnus=20B=C3=A4ck?= <magnus@noun.se>
Date: Thu, 2 Jan 2020 21:43:33 +0100
Subject: [PATCH] Enable prealloc checker and fix existing violations

---
 .golangci.yml               | 1 +
 logstash-filter-verifier.go | 2 +-
 testcase/discover.go        | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/.golangci.yml b/.golangci.yml
index 9ae5609..48f2589 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -9,6 +9,7 @@ linters:
     - gosimple
     - ineffassign
     - misspell
+    - prealloc
     - staticcheck
     - structcheck
     - typecheck
diff --git a/logstash-filter-verifier.go b/logstash-filter-verifier.go
index bdae7c6..36b0139 100644
--- a/logstash-filter-verifier.go
+++ b/logstash-filter-verifier.go
@@ -162,7 +162,7 @@ func runTests(inv *logstash.Invocation, tests []testcase.TestCaseSet, diffComman
 // the actual events against the expected set. Returns an error if
 // at least one test case fails or if there's a problem running the tests.
 func runParallelTests(inv *logstash.Invocation, tests []testcase.TestCaseSet, diffCommand []string, keptEnvVars []string) error {
-	var testStreams []*logstash.TestStream
+	testStreams := make([]*logstash.TestStream, 0, len(tests))
 
 	badCodecs := map[string]string{
 		"json":  "json_lines",
diff --git a/testcase/discover.go b/testcase/discover.go
index a356038..d27a4d1 100644
--- a/testcase/discover.go
+++ b/testcase/discover.go
@@ -31,7 +31,7 @@ func discoverTestDirectory(path string) ([]TestCaseSet, error) {
 	if err != nil {
 		return nil, fmt.Errorf("Error discovering test case files: %s", err)
 	}
-	var result []TestCaseSet
+	result := make([]TestCaseSet, 0, len(files))
 	for _, f := range files {
 		if f.IsDir() || (!strings.HasSuffix(f.Name(), ".json") && !strings.HasSuffix(f.Name(), ".yaml") && !strings.HasSuffix(f.Name(), ".yml")) {
 			continue