add CI script

.github/workflows/build.yaml

@@ -0,0 +1,42 @@
+name: build
+on:
+    push:
+        branches:
+            - "**"
+jobs:
+    build:
+        runs-on: ${{ matrix.os }}
+        strategy:
+            matrix:
+                os:
+                    - ubuntu-latest
+                    - macOS-latest
+        steps:
+            - name: setup go
+              uses: actions/setup-go@v1
+              with:
+                  go-version: 1.14
+
+            - name: checkout
+              uses: actions/checkout@v1
+
+            - name: setup docker
+              uses: docker-practice/actions-setup-docker@master
+              if: matrix.os == 'macOS-latest'
+
+            - name: build
+              run: make
+
+            - name: Convert coverage to lcov
+              uses: jandelgado/gcov2lcov-action@v1.0.0
+              with:
+                  infile: coverage.out
+                  outfile: coverage.lcov
+              if: "matrix.os == 'ubuntu-latest'"
+
+            - name: coveralls
+              uses: coverallsapp/github-action@v1.0.1
+              with:
+                  github-token: ${{ secrets.github_token }}
+                  path-to-lcov: coverage.lcov
+              if: "matrix.os == 'ubuntu-latest'"

.gitignore

@@ -1,3 +1,5 @@
+/flaver
+
 ### https://raw.github.com/github/gitignore/218a941be92679ce67d0484547e3e142b2f5f6f0/Go.gitignore
 
 # Binaries for programs and plugins

cmd/commands/root.go

@@ -24,6 +24,9 @@ func performEach(command *cobra.Command, arg string, ec *errors.Center) ([]flave
 		return flaverObject.FindAll(repo)
 	}
 	release, err := flaverObject.Find(repo)
+	if release == nil {
+		return []flaver.Release{}, err
+	}
 	return []flaver.Release{release}, err
 }
 

github.go

@@ -32,7 +32,7 @@ type GitHubFlaver struct {
 
 func (ghf *GitHubFlaver) Find(repo *Repository) (Release, error) {
 	releases, err := ghf.FindAll(repo)
-	if err == nil {
+	if err == nil && len(releases) > 0 {
 		return releases[0], err
 	}
 	return nil, err

gitlab.go

@@ -35,7 +35,7 @@ type GitLabFlaver struct {
 
 func (glf *GitLabFlaver) Find(repo *Repository) (Release, error) {
 	releases, err := glf.FindAll(repo)
-	if err == nil {
+	if err == nil && len(releases) > 0 {
 		return releases[0], err
 	}
 	return nil, err