diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 1db330f..5d2c967 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -190,6 +190,33 @@ jobs:
       if: startsWith(matrix.os, 'windows') && matrix.ruby == 'jruby'
       run: gem install sassc
 
+  testDotRubyVersion:
+    name: "Test .ruby-version"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: echo "ruby-3.4.0" > .ruby-version
+      - uses: ./
+      - run: ruby -v | grep -F "ruby 3.4.0"
+
+  testToolVersions:
+    name: "Test .tool-versions"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: echo "nodejs 16.0.0\nruby   3.4.0" > .tool-versions
+      - uses: ./
+      - run: ruby -v | grep -F "ruby 3.4.0"
+
+  testMise:
+    name: "Test mise.toml"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: echo "[tools]\nnode = '18'\nruby = '3.4.0'" > mise.toml
+      - uses: ./
+      - run: ruby -v | grep -F "ruby 3.4.0"
+
   testNoGemfile:
     name: "Test with no Gemfile"
     runs-on: ubuntu-latest
diff --git a/dist/index.js b/dist/index.js
index cae2289..1762cf8 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -74932,13 +74932,15 @@ function parseRubyEngineAndVersion(rubyVersion) {
     console.log(`Using ${rubyVersion} as input from file .ruby-version`)
   } else if (rubyVersion === '.tool-versions') { // Read from .tool-versions
     const toolVersions = fs.readFileSync('.tool-versions', 'utf8').trim()
-    const rubyLine = toolVersions.split(/\r?\n/).filter(e => /^ruby\s/.test(e))[0]
-    rubyVersion = rubyLine.split(/\s+/)[1]
+    const regexp = /^ruby\s+(\S+)/
+    const rubyLine = toolVersions.split(/\r?\n/).filter(e => regexp.test(e))[0]
+    rubyVersion = rubyLine.match(regexp)[1]
     console.log(`Using ${rubyVersion} as input from file .tool-versions`)
   } else if (rubyVersion === 'mise.toml') { // Read from mise.toml
     const toolVersions = fs.readFileSync('mise.toml', 'utf8').trim()
-    const rubyLine = toolVersions.split(/\r?\n/).filter(e => /^ruby\s*=\s*/.test(e))[0]
-    rubyVersion = rubyLine.match(/^ruby\s*=\s*['"](.+)['"]$/)[1]
+    const regexp = /^ruby\s*=\s*['"](.+)['"]$/
+    const rubyLine = toolVersions.split(/\r?\n/).filter(e => regexp.test(e))[0]
+    rubyVersion = rubyLine.match(regexp)[1]
     console.log(`Using ${rubyVersion} as input from file mise.toml`)
   }
 
diff --git a/index.js b/index.js
index 7ea9672..1bba0a4 100644
--- a/index.js
+++ b/index.js
@@ -129,13 +129,15 @@ function parseRubyEngineAndVersion(rubyVersion) {
     console.log(`Using ${rubyVersion} as input from file .ruby-version`)
   } else if (rubyVersion === '.tool-versions') { // Read from .tool-versions
     const toolVersions = fs.readFileSync('.tool-versions', 'utf8').trim()
-    const rubyLine = toolVersions.split(/\r?\n/).filter(e => /^ruby\s/.test(e))[0]
-    rubyVersion = rubyLine.split(/\s+/)[1]
+    const regexp = /^ruby\s+(\S+)/
+    const rubyLine = toolVersions.split(/\r?\n/).filter(e => regexp.test(e))[0]
+    rubyVersion = rubyLine.match(regexp)[1]
     console.log(`Using ${rubyVersion} as input from file .tool-versions`)
   } else if (rubyVersion === 'mise.toml') { // Read from mise.toml
     const toolVersions = fs.readFileSync('mise.toml', 'utf8').trim()
-    const rubyLine = toolVersions.split(/\r?\n/).filter(e => /^ruby\s*=\s*/.test(e))[0]
-    rubyVersion = rubyLine.match(/^ruby\s*=\s*['"](.+)['"]$/)[1]
+    const regexp = /^ruby\s*=\s*['"](.+)['"]$/
+    const rubyLine = toolVersions.split(/\r?\n/).filter(e => regexp.test(e))[0]
+    rubyVersion = rubyLine.match(regexp)[1]
     console.log(`Using ${rubyVersion} as input from file mise.toml`)
   }