Fix bin/dev showing 'Process Manager Not Found' when overmind exists but exits

lib/react_on_rails/dev/process_manager.rb

@@ -36,9 +36,20 @@ def run_with_process_manager(procfile)
           FileManager.cleanup_stale_files
 
           # Try process managers in order of preference
-          return if run_process_if_available("overmind", ["start", "-f", procfile])
-          return if run_process_if_available("foreman", ["start", "-f", procfile])
+          # run_process_if_available returns:
+          #   - true/false (exit status) if process was found and executed
+          #   - nil if process was not found
+          overmind_result = run_process_if_available("overmind", ["start", "-f", procfile])
+          return if overmind_result == true # Overmind ran successfully
 
+          foreman_result = run_process_if_available("foreman", ["start", "-f", procfile])
+          return if foreman_result == true # Foreman ran successfully
+
+          # If either process was found but exited with error, don't show "not found" message
+          # The process manager itself will have shown its own error message
+          exit 1 if overmind_result == false || foreman_result == false
+
+          # Neither process manager was found
           show_process_manager_installation_help
           exit 1
         end
@@ -73,7 +84,10 @@ def version_flags_for(process)
         end
 
         # Try to run a process if it's available, with intelligent fallback strategy
-        # Returns true if process was found and executed, false if not available
+        # Returns:
+        #   - true if process ran and exited successfully (exit code 0)
+        #   - false if process ran but exited with error (non-zero exit code)
+        #   - nil if process was not found/available
         def run_process_if_available(process, args)
           # First attempt: try in current context (works for bundled processes)
           return system(process, *args) if installed?(process)
@@ -82,7 +96,7 @@ def run_process_if_available(process, args)
           return run_process_outside_bundle(process, args) if process_available_in_system?(process)
 
           # Process not available in either context
-          false
+          nil
         end
 
         # Run a process outside of bundler context

sig/react_on_rails/dev/process_manager.rbs

@@ -11,7 +11,7 @@ module ReactOnRails
 
       def self.installed_in_current_context?: (String) -> bool
       def self.version_flags_for: (String) -> Array[String]
-      def self.run_process_if_available: (String, Array[String]) -> bool
+      def self.run_process_if_available: (String, Array[String]) -> (bool | nil)
       def self.run_process_outside_bundle: (String, Array[String]) -> bool
       def self.process_available_in_system?: (String) -> bool
       def self.with_unbundled_context: () { () -> untyped } -> untyped

spec/react_on_rails/dev/process_manager_spec.rb

@@ -71,19 +71,63 @@
     end
 
     it "uses foreman when overmind not available and foreman is available" do
+      expect(described_class).to receive(:run_process_if_available)
+        .with("overmind", ["start", "-f", "Procfile.dev"]).and_return(nil)
+      expect(described_class).to receive(:run_process_if_available)
+        .with("foreman", ["start", "-f", "Procfile.dev"]).and_return(true)
+
+      described_class.run_with_process_manager("Procfile.dev")
+    end
+
+    it "exits silently when overmind is installed but exits with error (foreman not found)" do
+      expect(described_class).to receive(:run_process_if_available)
+        .with("overmind", ["start", "-f", "Procfile.dev"]).and_return(false)
+      expect(described_class).to receive(:run_process_if_available)
+        .with("foreman", ["start", "-f", "Procfile.dev"]).and_return(nil)
+      expect(described_class).not_to receive(:show_process_manager_installation_help)
+      expect_any_instance_of(Kernel).to receive(:exit).with(1).and_raise(SystemExit)
+
+      expect { described_class.run_with_process_manager("Procfile.dev") }.to raise_error(SystemExit)
+    end
+
+    it "exits silently when overmind fails but foreman succeeds" do
       expect(described_class).to receive(:run_process_if_available)
         .with("overmind", ["start", "-f", "Procfile.dev"]).and_return(false)
       expect(described_class).to receive(:run_process_if_available)
         .with("foreman", ["start", "-f", "Procfile.dev"]).and_return(true)
+      expect(described_class).not_to receive(:show_process_manager_installation_help)
+      expect_any_instance_of(Kernel).not_to receive(:exit)
 
       described_class.run_with_process_manager("Procfile.dev")
     end
 
-    it "exits with error when no process manager available" do
+    it "exits silently when overmind fails and foreman also fails" do
       expect(described_class).to receive(:run_process_if_available)
         .with("overmind", ["start", "-f", "Procfile.dev"]).and_return(false)
       expect(described_class).to receive(:run_process_if_available)
         .with("foreman", ["start", "-f", "Procfile.dev"]).and_return(false)
+      expect(described_class).not_to receive(:show_process_manager_installation_help)
+      expect_any_instance_of(Kernel).to receive(:exit).with(1).and_raise(SystemExit)
+
+      expect { described_class.run_with_process_manager("Procfile.dev") }.to raise_error(SystemExit)
+    end
+
+    it "exits silently when overmind not found but foreman exits with error" do
+      expect(described_class).to receive(:run_process_if_available)
+        .with("overmind", ["start", "-f", "Procfile.dev"]).and_return(nil)
+      expect(described_class).to receive(:run_process_if_available)
+        .with("foreman", ["start", "-f", "Procfile.dev"]).and_return(false)
+      expect(described_class).not_to receive(:show_process_manager_installation_help)
+      expect_any_instance_of(Kernel).to receive(:exit).with(1).and_raise(SystemExit)
+
+      expect { described_class.run_with_process_manager("Procfile.dev") }.to raise_error(SystemExit)
+    end
+
+    it "exits with error when no process manager available" do
+      expect(described_class).to receive(:run_process_if_available)
+        .with("overmind", ["start", "-f", "Procfile.dev"]).and_return(nil)
+      expect(described_class).to receive(:run_process_if_available)
+        .with("foreman", ["start", "-f", "Procfile.dev"]).and_return(nil)
       expect(described_class).to receive(:show_process_manager_installation_help)
       expect_any_instance_of(Kernel).to receive(:exit).with(1)
 
@@ -117,12 +161,12 @@
       expect(result).to be true
     end
 
-    it "returns false when process not available anywhere" do
+    it "returns nil when process not available anywhere" do
       allow(described_class).to receive(:installed?).with("nonexistent").and_return(false)
       allow(described_class).to receive(:process_available_in_system?).with("nonexistent").and_return(false)
 
       result = described_class.send(:run_process_if_available, "nonexistent", ["start"])
-      expect(result).to be false
+      expect(result).to be_nil
     end
   end