Conform to all linter warnings/advice

Summary:
Fixed all linter warnings and advice except for vet's rule about unkeyed
composite literals which was disabled via a `-composites=false` flag in
`.arclint`. Most unkeyed literals (e.g. `build.Run{"command"}`) in this
project just seem too usefully succinct compared to their more verbose
keyed counterparts.

Depends on D841

Test Plan: Run `arc lint --everything` and verify there are no warnings or advice.

Reviewers: thcipriani, hashar, #release-engineering-team

Reviewed By: thcipriani, hashar, #release-engineering-team

Tags: #release-engineering-team

Differential Revision: https://phabricator.wikimedia.org/D845

4 files changed, 24 insertions, 24 deletions

diff --git a/config/common.go b/config/common.go
index 11357d8..62fb483 100644
--- a/config/common.go
+++ b/config/common.go
@@ -18,18 +18,18 @@ type CommonConfig struct {
 
 // Merge takes another CommonConfig and merges its fields this one's.
 //
-func (cc1 *CommonConfig) Merge(cc2 CommonConfig) {
+func (cc *CommonConfig) Merge(cc2 CommonConfig) {
 	if cc2.Base != "" {
-		cc1.Base = cc2.Base
+		cc.Base = cc2.Base
 	}
 
-	cc1.Apt.Merge(cc2.Apt)
-	cc1.Node.Merge(cc2.Node)
-	cc1.Runs.Merge(cc2.Runs)
-	cc1.SharedVolume.Merge(cc2.SharedVolume)
+	cc.Apt.Merge(cc2.Apt)
+	cc.Node.Merge(cc2.Node)
+	cc.Runs.Merge(cc2.Runs)
+	cc.SharedVolume.Merge(cc2.SharedVolume)
 
-	if len(cc1.EntryPoint) < 1 {
-		cc1.EntryPoint = cc2.EntryPoint
+	if len(cc.EntryPoint) < 1 {
+		cc.EntryPoint = cc2.EntryPoint
 	}
 }
 
diff --git a/config/reader.go b/config/reader.go
index 7aa060d..7aaa22e 100644
--- a/config/reader.go
+++ b/config/reader.go
@@ -72,7 +72,7 @@ func ReadConfigFile(path string) (*Config, error) {
 
 	if err != nil {
 		return nil, err
-	} else {
-		return ReadConfig(data)
 	}
+
+	return ReadConfig(data)
 }
diff --git a/config/runs.go b/config/runs.go
index ef9f4ea..5986112 100644
--- a/config/runs.go
+++ b/config/runs.go
@@ -17,8 +17,8 @@ const LocalLibPrefix = "/opt/lib"
 type RunsConfig struct {
 	In          string            `yaml:"in"`          // working directory
 	As          string            `yaml:"as"`          // unprivileged user
-	Uid         int               `yaml:"uid"`         // unprivileged UID
-	Gid         int               `yaml:"gid"`         // unprivileged GID
+	UID         int               `yaml:"uid"`         // unprivileged user ID
+	GID         int               `yaml:"gid"`         // unprivileged group ID
 	Environment map[string]string `yaml:"environment"` // environment variables
 }
 
@@ -33,11 +33,11 @@ func (run *RunsConfig) Merge(run2 RunsConfig) {
 	if run2.As != "" {
 		run.As = run2.As
 	}
-	if run2.Uid != 0 {
-		run.Uid = run2.Uid
+	if run2.UID != 0 {
+		run.UID = run2.UID
 	}
-	if run2.Gid != 0 {
-		run.Gid = run2.Gid
+	if run2.GID != 0 {
+		run.GID = run2.GID
 	}
 
 	if run.Environment == nil {
@@ -55,9 +55,9 @@ func (run *RunsConfig) Merge(run2 RunsConfig) {
 func (run RunsConfig) Home() string {
 	if run.As == "" {
 		return "/root"
-	} else {
-		return "/home/" + run.As
 	}
+
+	return "/home/" + run.As
 }
 
 // InstructionsForPhase injects build instructions related to the runtime
@@ -92,9 +92,9 @@ func (run RunsConfig) InstructionsForPhase(phase build.Phase) []build.Instructio
 		if run.As != "" {
 			runAll.Runs = append(runAll.Runs,
 				build.Run{"groupadd -o -g %s -r",
-					[]string{strconv.Itoa(run.Gid), run.As}},
+					[]string{strconv.Itoa(run.GID), run.As}},
 				build.Run{"useradd -o -m -d %s -r -g %s -u %s",
-					[]string{run.Home(), run.As, strconv.Itoa(run.Uid), run.As}},
+					[]string{run.Home(), run.As, strconv.Itoa(run.UID), run.As}},
 				build.Run{"chown %s:%s",
 					[]string{run.As, run.As, LocalLibPrefix}},
 			)
diff --git a/config/runs_test.go b/config/runs_test.go
index c8bb2bc..3aa8825 100644
--- a/config/runs_test.go
+++ b/config/runs_test.go
@@ -28,8 +28,8 @@ func TestRunsConfig(t *testing.T) {
 
 	assert.Equal(t, "someuser", variant.Runs.As)
 	assert.Equal(t, "/some/directory", variant.Runs.In)
-	assert.Equal(t, 666, variant.Runs.Uid)
-	assert.Equal(t, 777, variant.Runs.Gid)
+	assert.Equal(t, 666, variant.Runs.UID)
+	assert.Equal(t, 777, variant.Runs.GID)
 	assert.Equal(t, map[string]string{"FOO": "bar"}, variant.Runs.Environment)
 }
 
@@ -49,8 +49,8 @@ func TestRunsConfigInstructions(t *testing.T) {
 	cfg := config.RunsConfig{
 		As:  "someuser",
 		In:  "/some/directory",
-		Uid: 666,
-		Gid: 777,
+		UID: 666,
+		GID: 777,
 		Environment: map[string]string{
 			"fooname": "foovalue",
 			"barname": "barvalue",