add new parameter

.github/workflows/codeql-analysis.yml

@@ -27,6 +27,7 @@ jobs:
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v1
 
+
         # Override language selection by uncommenting this and choosing your languages
         # with:
         #   languages: go, javascript, csharp, python, cpp, java

README.md

@@ -22,6 +22,16 @@ The name of the head reference. Default `${{github.sha}}`.
 
 The name of the second branch. Defaults to the `tag_name` of the latest release.
 
+## `firstRelease`
+
+The flag of base-ref setting when no release. Default `"commit"`.
+
+If your repository has never published a release,
+you can set the base reference through this parameter.
+
+When this parameter is set to "commit", the base reference will be set to initial commit.
+When this parameter is set to "tag", the base reference will be set to the latest tag.
+
 ## Outputs
 
 ### `changelog`

action.yml

@@ -14,6 +14,17 @@ inputs:
     description: 'The name of the base reference'
     default: ''
     required: false
+  firstRelease:
+    description: >
+      The flag of base-ref setting when no release. Default `"commit"`.
+
+      If your repository has never published a release,
+      you can set the base reference through this parameter.
+
+      When this parameter is set to "commit", the base reference will be set to initial commit.
+      When this parameter is set to "tag", the base reference will be set to the latest tag.
+    default: 'commit'
+    required: false
 outputs:
   changelog:
     description: 'Markdown formatted changelog'

changelog.sh

@@ -12,15 +12,23 @@ git fetch --depth=1 origin +refs/tags/*:refs/tags/* 1>&2
 git fetch --no-tags --prune --depth=1 origin +refs/heads/*:refs/remotes/origin/* 1>&2
 git fetch --prune --unshallow 1>&2
 
-# if folks don't have a base ref to compare against just use the initial
-# commit. This will show all the changes since the beginning but I can't
-# think of a better default.
-if [ -z "$base_ref" ]
+# If there is no release for comparison, the initial commit is used when "$commit"
+# is obtained, This will show all the changes since the beginning.
+# the latest tag is used when "$tag" is obtained, and the default is "$commit".
+if [ "$base_ref" = "\$commit" ]
 then
   base_ref=$(git rev-list --max-parents=0 HEAD)
+  flag=$head_ref # Include the first commit
+elif [ "$base_ref" = "\$tag" ]
+then
+  tagName=$(git describe --tags --abbrev=0 $(git rev-list --tags --max-count=1 --skip=1))
+  base_ref=$(git rev-list ${tagName} --max-count=1)
+  flag="${base_ref}...${head_ref}"
+else
+  flag="${base_ref}...${head_ref}"
 fi
 
-log=$(git log "${base_ref}...${head_ref}" \
+log=$(git log "${flag}" \
   --pretty=format:"* [\`%h\`](http://github.com/${repo_url}/commit/%H) - %s" \
   --reverse)
 

dist/changelog.sh

@@ -12,15 +12,23 @@ git fetch --depth=1 origin +refs/tags/*:refs/tags/* 1>&2
 git fetch --no-tags --prune --depth=1 origin +refs/heads/*:refs/remotes/origin/* 1>&2
 git fetch --prune --unshallow 1>&2
 
-# if folks don't have a base ref to compare against just use the initial
-# commit. This will show all the changes since the beginning but I can't
-# think of a better default.
-if [ -z "$base_ref" ]
+# If there is no release for comparison, the initial commit is used when "$commit"
+# is obtained, This will show all the changes since the beginning.
+# the latest tag is used when "$tag" is obtained, and the default is "$commit".
+if [ "$base_ref" = "\$commit" ]
 then
   base_ref=$(git rev-list --max-parents=0 HEAD)
+  flag=$head_ref # Include the first commit
+elif [ "$base_ref" = "\$tag" ]
+then
+  tagName=$(git describe --tags --abbrev=0 $(git rev-list --tags --max-count=1 --skip=1))
+  base_ref=$(git rev-list ${tagName} --max-count=1)
+  flag="${base_ref}...${head_ref}"
+else
+  flag="${base_ref}...${head_ref}"
 fi
 
-log=$(git log "${base_ref}...${head_ref}" \
+log=$(git log "${flag}" \
   --pretty=format:"* [\`%h\`](http://github.com/${repo_url}/commit/%H) - %s" \
   --reverse)