Display react-native-cli version on initialisation for non-expo projects

Author: Rishabh Karnad

package.json

@@ -36,6 +36,7 @@
     "chalk": "^2.4.2",
     "commander": "^2.20.0",
     "ora": "^3.4.0",
-    "prompt": "^1.0.0"
+    "prompt": "^1.0.0",
+    "semver-regex": "^3.1.0"
   }
 }

src/index.js

@@ -36,11 +36,16 @@ program
         );
       }
     } else {
-      if (!validationObjects.getReactNativeCLIifAvailable()) {
+      const reactNativeCLIVersion = validationObjects.getReactNativeCLIifAvailable();
+      if (!reactNativeCLIVersion) {
         terminateTheProcess(
-          "Please globally install react-native-cli dependency"
+          "Please globally install react-native-cli"
         );
         return;
+      } else {
+        console.log(
+          chalk.cyan("Using globally installed react-native-cli " + reactNativeCLIVersion + "\n"),
+        );
       }
     }
     const isProjectNameValidResponse = validationObjects.isProjectNameValid(

src/utils/validation.js

@@ -1,5 +1,7 @@
 const chalk = require("chalk");
 const execSync = require("child_process").execSync;
+const semverRegex = require('semver-regex');
+
 const constantObjects = require("./constants");
 
 function isProjectNameValidForCrna(projectName) {
@@ -73,26 +75,23 @@ function getCrnaVersionIfAvailable() {
 }
 
 function getReactNativeCLIifAvailable() {
-  let crnaVersion = null;
-  try {
+  // Get package version command and discard stderr on *nix systems
+  const processCommand = process.platform.startsWith("win")
+    ? `${constantObjects.rnPackageName} --version`
+    : `${constantObjects.rnPackageName} --version 2>/dev/null`
+
+    try {
     // execSync returns a Buffer -> convert to string
-    if (process.platform.startsWith("win")) {
-      crnaVersion = (
-        execSync(`${constantObjects.rnPackageName} --version`).toString() ||
-        ""
-      ).trim();
-    } else {
-      crnaVersion = (
-        execSync(
-          `${constantObjects.rnPackageName} --version 2>/dev/null`
-        ).toString() || ""
-      ).trim();
-    }
+    const commandResult = (execSync(processCommand).toString() || "").trim();
+    const regexMatches = commandResult.match(semverRegex());
+    const packageSemver = regexMatches.length > 0
+      ? regexMatches[0] // longest first match
+      : "";
+    return packageSemver;
   } catch (error) {
     console.log(chalk.red("Error In Getting React Native Package Version"));
     return null;
   }
-  return crnaVersion;
 }
 
 module.exports = {

yarn.lock

@@ -288,6 +288,11 @@ rimraf@2.x.x:
   dependencies:
     glob "^7.1.3"
 
+semver-regex@^3.1.0:
+  version "3.1.0"
+  resolved "https://registry.yarnpkg.com/semver-regex/-/semver-regex-3.1.0.tgz#23368cb577bf2668e78bf9c3e8e519fc029ca069"
+  integrity sha512-xJqZonbAohJmpogzq1Mx7DB4DT3LO+sG5J4i/rcRyZ527dcUqsTVb5T0vM5gwOBf3KO0v7i94EpbdvwSukJyAQ==
+
 signal-exit@^3.0.2:
   version "3.0.2"
   resolved "https://registry.yarnpkg.com/signal-exit/-/signal-exit-3.0.2.tgz#b5fdc08f1287ea1178628e415e25132b73646c6d"