Export BuildCodegenCLITask to its own task class

Summary:
This diff moves `BuildCodegenCLITask` from being inlined to have its own task definition
I've also cleaned up the task body and refactored a bit how we do the CLI invocation.

Changelog:
[Internal] [Changed] - Export `BuildCodegenCLITask` to its own task class

Reviewed By: ShikaSD

Differential Revision: D31016610

fbshipit-source-id: 8407fc2a62ea473daa775196925c1b9b6f4f2f4b

packages/react-native-gradle-plugin/src/main/java/com/facebook/react/codegen/plugin/CodegenPlugin.java

@@ -10,13 +10,12 @@ package com.facebook.react.codegen.plugin;
 import com.android.build.gradle.BaseExtension;
 import com.facebook.react.ReactExtension;
 import com.facebook.react.codegen.generator.JavaGenerator;
+import com.facebook.react.tasks.BuildCodegenCLITask;
 import com.facebook.react.utils.GradleUtils;
 import com.facebook.react.utils.PathUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.io.File;
-import java.io.IOException;
-import org.apache.tools.ant.taskdefs.condition.Os;
 import org.gradle.api.GradleException;
 import org.gradle.api.Project;
 import org.gradle.api.Task;
@@ -40,55 +39,16 @@ public class CodegenPlugin {
     // 2. Task: produce schema from JS files.
     String os = System.getProperty("os.name").toLowerCase();
 
-    TaskProvider<Exec> buildCodegenTask =
+    TaskProvider<BuildCodegenCLITask> buildCodegenTask =
         project
             .getTasks()
             .register(
                 "buildCodegenCLI",
-                Exec.class,
+                BuildCodegenCLITask.class,
                 task -> {
-                  // This task is required when using react-native-codegen from source, instead of
-                  // npm.
-                  File codegenRoot = extension.getCodegenDir().getAsFile().get();
-
-                  task.getInputs()
-                      .files(
-                          project.file(new File(codegenRoot, "scripts")),
-                          project.file(new File(codegenRoot, "src")),
-                          project.file(new File(codegenRoot, "package.json")),
-                          project.file(new File(codegenRoot, ".babelrc")),
-                          project.file(new File(codegenRoot, ".prettierrc")));
-
-                  File libDir = project.file(new File(codegenRoot, "lib"));
-                  File nodeModulesDir = project.file(new File(codegenRoot, "node_modules"));
-                  task.getOutputs().dirs(libDir, nodeModulesDir);
-
-                  task.onlyIf(
-                      spec -> {
-                        File cliDir = new File(codegenRoot, "lib/cli/");
-                        return !cliDir.exists() || cliDir.listFiles().length == 0;
-                      });
-
-                  if (Os.isFamily(Os.FAMILY_WINDOWS)) {
-                    // Convert path to Linux format: use canonical path to strip it off relative
-                    // elements in the middle of the string.
-                    // Then replace baskslashes with slashes, remove leading colon, add leading
-                    // slash.
-                    // Eg. D:\path1\sub2/.. -> /D/path1/path2
-                    try {
-                      String canonicalPath = codegenRoot.getCanonicalPath();
-                      String linuxPath = "/" + canonicalPath.replace('\\', '/').replace(":", "");
-
-                      // Get the location of bash in the system; assume environment variable created
-                      // to store it.
-                      String bashHome = System.getenv("REACT_WINDOWS_BASH");
-                      task.commandLine(bashHome, "-c", linuxPath + "/scripts/oss/build.sh");
-                    } catch (IOException e) {
-                      e.printStackTrace();
-                    }
-                  } else {
-                    task.commandLine(codegenRoot.getAbsolutePath() + "/scripts/oss/build.sh");
-                  }
+                  task.getCodegenDir().set(extension.getCodegenDir());
+                  String bashWindowsHome = (String) project.findProperty("REACT_WINDOWS_BASH");
+                  task.getBashWindowsHome().set(bashWindowsHome);
                 });
 
     project

packages/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/tasks/BuildCodegenCLITask.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.tasks
+
+import com.facebook.react.utils.Os.unixifyPath
+import com.facebook.react.utils.windowsAwareBashCommandLine
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.file.FileCollection
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.*
+
+/**
+ * A Task that will call the `scripts/oss/build.sh` script to trigger the creation of the codegen
+ * lib artifacts.
+ *
+ * NOTE: This task is required when using react-native-codegen from source, instead of npm.
+ */
+abstract class BuildCodegenCLITask : Exec() {
+
+  @get:Internal abstract val codegenDir: DirectoryProperty
+
+  @get:Internal abstract val bashWindowsHome: Property<String>
+
+  @get:InputFiles
+  val input: FileCollection =
+      codegenDir.files("scripts", "src", "package.json", ".babelrc", ".prettierrc")
+
+  @get:OutputFiles val output: FileCollection = codegenDir.files("lib", "node_modules")
+
+  init {
+    // We need this condition as we want a single instance of BuildCodegenCLITask to execute
+    // per project. Therefore we can safely skip the task if the lib/cli/ folder is available.
+    onlyIf {
+      val cliDir = codegenDir.file("lib/cli/").get().asFile
+      !cliDir.exists() || cliDir.listFiles()?.size == 0
+    }
+  }
+
+  override fun exec() {
+    commandLine(
+        windowsAwareBashCommandLine(
+            codegenDir.asFile.get().canonicalPath.unixifyPath().plus(BUILD_SCRIPT_PATH),
+            bashWindowsHome = bashWindowsHome.orNull,
+        ))
+    super.exec()
+  }
+
+  companion object {
+    private const val BUILD_SCRIPT_PATH = "/scripts/oss/build.sh"
+  }
+}

packages/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/utils/Os.kt

@@ -13,4 +13,13 @@ object Os {
 
   fun isWindows(): Boolean =
       System.getProperty("os.name")?.toLowerCase(Locale.ROOT)?.contains("windows") ?: false
+
+  fun String.unixifyPath() =
+      this.replace('\\', '/').replace(":", "").let {
+        if (!it.startsWith("/")) {
+          "/$it"
+        } else {
+          it
+        }
+      }
 }

packages/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/utils/TaskUtils.kt

@@ -13,3 +13,13 @@ internal fun windowsAwareCommandLine(vararg args: Any): List<Any> =
     } else {
       args.toList()
     }
+
+internal fun windowsAwareBashCommandLine(
+    vararg args: String,
+    bashWindowsHome: String? = null
+): List<String> =
+    if (Os.isWindows()) {
+      listOf(bashWindowsHome ?: "bash", "-c") + args
+    } else {
+      args.toList()
+    }

packages/react-native-gradle-plugin/src/test/kotlin/com/facebook/react/utils/OsTest.kt

@@ -10,6 +10,7 @@ package com.facebook.react.utils
 import com.facebook.react.tests.OS
 import com.facebook.react.tests.OsRule
 import com.facebook.react.tests.WithOs
+import com.facebook.react.utils.Os.unixifyPath
 import org.junit.Assert.*
 import org.junit.Rule
 import org.junit.Test
@@ -35,4 +36,18 @@ class OsTest {
   fun isWindows_onWindows_returnsTrue() {
     assertTrue(Os.isWindows())
   }
+
+  @Test
+  fun unixifyPath_withAUnixPath_doesNothing() {
+    val aUnixPath = "/just/a/unix/path.sh"
+
+    assertEquals(aUnixPath, aUnixPath.unixifyPath())
+  }
+
+  @Test
+  fun unixifyPath_withAWindowsPath_convertsItCorrectly() {
+    val aWindowsPath = "D:\\just\\a\\windows\\path\\"
+
+    assertEquals("/D/just/a/windows/path/", aWindowsPath.unixifyPath())
+  }
 }

packages/react-native-gradle-plugin/src/test/kotlin/com/facebook/react/utils/TaskUtilsTest.kt

@@ -41,4 +41,31 @@ class TaskUtilsTest {
   fun windowsAwareCommandLine_onWindows_prependsCmd() {
     assertEquals(listOf("cmd", "/c", "a", "b", "c"), windowsAwareCommandLine("a", "b", "c"))
   }
+
+  @Test
+  @WithOs(OS.MAC)
+  fun windowsAwareBashCommandLine_onMac_returnsTheList() {
+    assertEquals(
+        listOf("a", "b", "c"), windowsAwareBashCommandLine("a", "b", "c", bashWindowsHome = "abc"))
+  }
+
+  @Test
+  @WithOs(OS.UNIX)
+  fun windowsAwareBashCommandLine_onLinux_returnsTheList() {
+    assertEquals(listOf("a", "b", "c"), windowsAwareBashCommandLine("a", "b", "c"))
+  }
+
+  @Test
+  @WithOs(OS.WIN)
+  fun windowsAwareBashCommandLine_onWindows_prependsBash() {
+    assertEquals(listOf("bash", "-c", "a", "b", "c"), windowsAwareBashCommandLine("a", "b", "c"))
+  }
+
+  @Test
+  @WithOs(OS.WIN)
+  fun windowsAwareBashCommandLine_onWindows_prependsCustomBashPath() {
+    assertEquals(
+        listOf("/custom/bash", "-c", "a", "b", "c"),
+        windowsAwareBashCommandLine("a", "b", "c", bashWindowsHome = "/custom/bash"))
+  }
 }