cli: add 'which'

.vscode/launch.json

@@ -0,0 +1,25 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Minitest - all",
+            "type": "Ruby",
+            "request": "launch",
+            "useBundler": true,
+            "cwd": "${workspaceRoot}",
+            "program": "/usr/bin/rake",
+            "args": ["test"]
+        },
+        {
+            "name": "Minitest - active tasks only",
+            "type": "Ruby",
+            "request": "launch",
+            "useBundler": true,
+            "cwd": "${workspaceRoot}",
+            "program": "${file}"
+        }
+    ]
+}

lib/autoproj/cli/main.rb

@@ -454,6 +454,12 @@ def exec(*args)
                 require 'autoproj/cli/exec'
                 CLI::Exec.new.run(*args)
             end
+
+            desc 'which', "resolves the full path to a command within the Autoproj workspace"
+            def which(cmd)
+                require 'autoproj/cli/which'
+                CLI::Which.new.run(cmd)
+            end
         end
     end
 end

lib/autoproj/cli/which.rb

@@ -0,0 +1,34 @@
+require 'autoproj/cli/inspection_tool'
+module Autoproj
+    module CLI
+        class Which < InspectionTool
+            def run(cmd)
+                initialize_and_load
+                finalize_setup(Array.new)
+
+                # Resolve the command using the PATH if present
+                env = ws.full_env
+                absolute =
+                    if Pathname.new(cmd).absolute?
+                        File.expand_path(cmd)
+                    else
+                        env.find_in_path(cmd)
+                    end
+
+                if absolute
+                    if !File.file?(absolute)
+                        Autoproj.error "given command `#{absolute}` does not exist"
+                        exit 1
+                    else
+                        puts absolute
+                    end
+                else
+                    Autoproj.error "cannot resolve `#{cmd}` in the workspace"
+                    exit 1
+                end
+            end
+        end
+    end
+end
+
+

test/cli/test_which.rb

@@ -0,0 +1,53 @@
+require 'autoproj/test'
+require 'autoproj/cli/which'
+
+module Autoproj
+    module CLI
+        describe Which do
+            include Autoproj::SelfTest;
+            before do
+                ws_create
+                @cli = Which.new(ws)
+                flexmock(@cli).should_receive(:initialize_and_load)
+            end
+
+            it "displays a given full path if it exists, regardless of PATH" do
+                ws.env.clear 'PATH'
+                path = File.join(ws.root_dir, 'test')
+                FileUtils.touch path
+                out, err = capture_io do
+                    @cli.run path
+                end
+                assert_equal "#{path}\n", out
+            end
+
+            it "displays an error if a given full path does not exist, and exits with error" do
+                path = File.join(ws.root_dir, 'test')
+                flexmock(Autoproj).should_receive(:error).with("given command `#{path}` does not exist").
+                    once
+                assert_raises(SystemExit) do
+                    @cli.run path
+                end
+            end
+
+            it "displays the resolved full path if found" do
+                ws.env.set 'PATH', ws.root_dir
+                path = File.join(ws.root_dir, 'test')
+                FileUtils.touch path
+                out, err = capture_io do
+                    @cli.run 'test'
+                end
+                assert_equal "#{path}\n", out
+            end
+
+            it "displays an error if the path cannot be resolved, and exits with error" do
+                flexmock(Autoproj).should_receive(:error).with("cannot resolve `test` in the workspace").
+                    once
+                assert_raises(SystemExit) do
+                    @cli.run 'test'
+                end
+            end
+        end
+    end
+end
+