Process builder will look for command on the path

docker-compose-rule-core/src/main/java/com/palantir/docker/compose/execution/DockerCommandLocator.java

@@ -15,8 +15,7 @@
  */
 package com.palantir.docker.compose.execution;
 
-import static java.util.Collections.singletonList;
-
+import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -28,13 +27,20 @@
 @Value.Immutable
 public abstract class DockerCommandLocator {
 
+    private static final List<String> MAC_SEARCH_LOCATIONS = ImmutableList.of("/usr/local/bin", "/usr/bin");
+
     protected abstract String command();
 
     @Value.Default
     protected boolean isWindows() {
         return SystemUtils.IS_OS_WINDOWS;
     }
 
+    @Value.Default
+    protected List<String> macSearchLocations() {
+        return MAC_SEARCH_LOCATIONS;
+    }
+
     @Value.Derived
     protected String executableName() {
         if (isWindows()) {
@@ -46,22 +52,17 @@ protected String executableName() {
     @Nullable
     protected abstract String locationOverride();
 
-    @Value.Derived
-    protected List<Path> searchLocations() {
-        if (locationOverride() == null) {
-            return DockerCommandLocations.pathLocations();
-        }
-        return singletonList(Paths.get(locationOverride()));
-    }
-
     public String getLocation() {
-        return searchLocations()
+        if (locationOverride() != null) {
+            return locationOverride();
+        }
+        return macSearchLocations()
                 .stream()
-                .map(p -> p.resolve(executableName()))
+                .map(p -> Paths.get(p, executableName()))
                 .filter(Files::exists)
                 .findFirst()
                 .map(Path::toString)
-                .orElseThrow(() -> new IllegalStateException("Could not find " + command() + " in " + searchLocations()));
+                .orElse(executableName());
     }
 
     public static ImmutableDockerCommandLocator.Builder forCommand(String command) {

docker-compose-rule-core/src/main/java/com/palantir/docker/compose/execution/DockerExecutable.java

@@ -59,4 +59,5 @@ public Process execute(String... commands) throws IOException {
     public static ImmutableDockerExecutable.Builder builder() {
         return ImmutableDockerExecutable.builder();
     }
+
 }

docker-compose-rule-core/src/test/java/com/palantir/docker/compose/execution/DockerCommandLocatorShould.java

@@ -15,16 +15,15 @@
  */
 package com.palantir.docker.compose.execution;
 
+import static java.util.Collections.singletonList;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.core.Is.is;
 
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
-import org.junit.contrib.java.lang.system.EnvironmentVariables;
 import org.junit.rules.ExpectedException;
 import org.junit.rules.TemporaryFolder;
 
@@ -36,63 +35,48 @@ public class DockerCommandLocatorShould {
 
     @Rule public ExpectedException exception = ExpectedException.none();
 
-    @Rule public EnvironmentVariables environmentVariables = new EnvironmentVariables();
-
-    private Path firstPathFolder;
-
-    private String commandFileLocation;
-    private String windowsCommandFileLocation;
-
-    @Before
-    public void setup() throws IOException {
-        firstPathFolder = folder.newFolder("first").toPath();
-
-        commandFileLocation = Files.createFile(firstPathFolder.resolve(command)).toString();
-        windowsCommandFileLocation = Files.createFile(firstPathFolder.resolve(windowsCommand)).toString();
-
-        environmentVariables.set("PATH", firstPathFolder.toString());
-    }
-
     @Test public void
-    provide_the_first_command_location() {
+    returns_the_command_name_when_no_other_paths_contain_command() {
         DockerCommandLocator locator = DockerCommandLocator.forCommand(command)
                 .isWindows(false)
                 .build();
-        assertThat(locator.getLocation(), is(commandFileLocation));
+
+        assertThat(locator.getLocation(), is(command));
     }
 
     @Test public void
-    provide_the_first_command_location_on_windows() {
+    returns_the_command_name_with_exe_on_windows_when_no_other_paths_contain_command() {
         DockerCommandLocator locator = DockerCommandLocator.forCommand(command)
                 .isWindows(true)
                 .build();
-        assertThat(locator.getLocation(), is(windowsCommandFileLocation));
+
+        assertThat(locator.getLocation(), is(windowsCommand));
     }
 
     @Test public void
-    fail_when_no_paths_contain_command() {
-        environmentVariables.set("PATH", null);
+    allow_the_path_to_be_overriden() throws IOException {
+        Path overrideFolder = folder.newFolder("override").toPath();
+        String overridenCommand = Files.createFile(overrideFolder.resolve(command)).toString();
 
         DockerCommandLocator locator = DockerCommandLocator.forCommand(command)
+                .locationOverride(overridenCommand)
                 .isWindows(false)
                 .build();
 
-        exception.expect(IllegalStateException.class);
-        exception.expectMessage("Could not find " + command + " in [/usr/local/bin, /usr/bin]");
-        locator.getLocation();
+        assertThat(locator.getLocation(), is(overridenCommand));
     }
 
     @Test public void
-    allow_the_path_to_be_overriden() throws IOException {
-        Path overrideFolder = folder.newFolder("override").toPath();
-        String overridenCommand = Files.createFile(overrideFolder.resolve(command)).toString();
+    search_in_known_mac_install_locations_for_the_command() throws IOException {
+        Path macSearchFolder = folder.newFolder("override").toPath();
+        String commandLocation = Files.createFile(macSearchFolder.resolve(command)).toString();
 
         DockerCommandLocator locator = DockerCommandLocator.forCommand(command)
-                .locationOverride(overrideFolder.toString())
+                .macSearchLocations(singletonList(macSearchFolder.toString()))
                 .isWindows(false)
                 .build();
 
-        assertThat(locator.getLocation(), is(overridenCommand));
+        assertThat(locator.getLocation(), is(commandLocation));
     }
 
 }