Introduce Scopes to track logical stack traces

This CL introduces a static class called Scope, which is
used the logical processing stack for data binding.
These scopes are used to generate meaningful error messages
when an error is detected.

Bug: 21953001
Change-Id: I5470a8c4ad94401d34a140762baae9d53c5a0402

4 files changed, 171 insertions, 12 deletions

diff --git a/compilationTests/build.gradle b/compilationTests/build.gradle
index abe046ac..e8b56dd9 100644
--- a/compilationTests/build.gradle
+++ b/compilationTests/build.gradle
@@ -12,4 +12,5 @@ dependencies {
     testCompile 'org.apache.commons:commons-lang3:3.3.2'
     testCompile 'commons-io:commons-io:2.4'
     testCompile 'commons-codec:commons-codec:1.10'
+    testCompile project(':compilerCommon')
 }
\ No newline at end of file
diff --git a/compilationTests/src/test/java/android/databinding/compilationTest/BaseCompilationTest.java b/compilationTests/src/test/java/android/databinding/compilationTest/BaseCompilationTest.java
index c390edcc..51925d58 100644
--- a/compilationTests/src/test/java/android/databinding/compilationTest/BaseCompilationTest.java
+++ b/compilationTests/src/test/java/android/databinding/compilationTest/BaseCompilationTest.java
@@ -19,6 +19,10 @@ package android.databinding.compilationTest;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
 import org.junit.Before;
+import org.junit.Rule;
+import org.junit.rules.TestName;
+
+import android.databinding.tool.store.Location;
 
 import java.io.File;
 import java.io.FileOutputStream;
@@ -29,8 +33,11 @@ import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.nio.file.attribute.PosixFilePermission;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.regex.Matcher;
@@ -42,6 +49,8 @@ import static org.junit.Assert.assertTrue;
 
 
 public class BaseCompilationTest {
+    @Rule
+    public TestName name = new TestName();
     static Pattern VARIABLES = Pattern.compile("!@\\{([A-Za-z0-9_-]*)}");
 
     public static final String KEY_MANIFEST_PACKAGE = "PACKAGE";
@@ -49,7 +58,7 @@ public class BaseCompilationTest {
     public static final String KEY_SETTINGS_INCLUDES = "SETTINGS_INCLUDES";
     public static final String DEFAULT_APP_PACKAGE = "com.android.databinding.compilationTest.test";
 
-    File testFolder = new File("./build/build-test");
+    protected final File testFolder = new File("./build/build-test");
 
     protected void copyResourceTo(String name, String path) throws IOException {
         copyResourceTo(name, new File(testFolder, path));
@@ -81,6 +90,36 @@ public class BaseCompilationTest {
         }
     }
 
+    /**
+     * Extracts the text in the given location from the the at the given application path.
+     * @param pathInApp The path, relative to the root of the application under test
+     * @param location The location to extract
+     * @return The string that is contained in the given location
+     * @throws IOException If file is invalid.
+     */
+    protected String extract(String pathInApp, Location location) throws IOException {
+        File file = new File(testFolder, pathInApp);
+        assertTrue(file.exists());
+        StringBuilder result = new StringBuilder();
+        List<String> lines = FileUtils.readLines(file);
+        for (int i = location.startLine; i <= location.endLine; i ++) {
+            if (i > location.startLine) {
+                result.append("\n");
+            }
+            String line = lines.get(i);
+            int start = 0;
+            if (i == location.startLine) {
+                start = location.startOffset;
+            }
+            int end = line.length() - 1; // inclusive
+            if (i == location.endLine) {
+                end = location.endOffset;
+            }
+            result.append(line.substring(start, end + 1));
+        }
+        return result.toString();
+    }
+
     protected void copyResourceTo(String name, File targetFile) throws IOException {
         File directory = targetFile.getParentFile();
         FileUtils.forceMkdir(directory);
@@ -179,13 +218,17 @@ public class BaseCompilationTest {
         copyResourceTo("/module_build.gradle", new File(moduleFolder, "build.gradle"), replacements);
     }
 
-    protected CompilationResult runGradle(String params) throws IOException, InterruptedException {
+    protected CompilationResult runGradle(String... params) throws IOException, InterruptedException {
         setExecutable();
         File pathToExecutable = new File(testFolder, "gradlew");
-        ProcessBuilder builder = new ProcessBuilder(pathToExecutable.getAbsolutePath(), params);
+        List<String> args = new ArrayList<>();
+        args.add(pathToExecutable.getAbsolutePath());
+        args.add("--project-cache-dir");
+        args.add(new File("../.caches/", name.getMethodName()).getAbsolutePath());
+        Collections.addAll(args, params);
+        ProcessBuilder builder = new ProcessBuilder(args);
         builder.environment().putAll(System.getenv());
         builder.directory(testFolder);
-        //builder.redirectErrorStream(true); // merges error and input streams
         Process process =  builder.start();
         String output = IOUtils.toString(process.getInputStream());
         String error = IOUtils.toString(process.getErrorStream());
diff --git a/compilationTests/src/test/java/android/databinding/compilationTest/CompilationResult.java b/compilationTests/src/test/java/android/databinding/compilationTest/CompilationResult.java
index 496550ba..f50755bd 100644
--- a/compilationTests/src/test/java/android/databinding/compilationTest/CompilationResult.java
+++ b/compilationTests/src/test/java/android/databinding/compilationTest/CompilationResult.java
@@ -16,6 +16,13 @@
 
 package android.databinding.compilationTest;
 
+import android.databinding.tool.processing.ScopedErrorReport;
+import android.databinding.tool.processing.ScopedException;
+
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+
 public class CompilationResult {
     public final int resultCode;
     public final String output;
@@ -34,4 +41,17 @@ public class CompilationResult {
     public boolean errorContainsText(String text) {
         return resultCode != 0 && error.indexOf(text) > 0;
     }
+
+    public ScopedException getBindingException() {
+        List<ScopedException> errors = ScopedException.extractErrors(error);
+        if (errors.isEmpty()) {
+            return null;
+        }
+        assertEquals(1, errors.size());
+        return errors.get(0);
+    }
+
+    public List<ScopedException> getBindingExceptions() {
+        return ScopedException.extractErrors(error);
+    }
 }
diff --git a/compilationTests/src/test/java/android/databinding/compilationTest/SimpleCompilationTest.java b/compilationTests/src/test/java/android/databinding/compilationTest/SimpleCompilationTest.java
index 6540e67d..877fe80a 100644
--- a/compilationTests/src/test/java/android/databinding/compilationTest/SimpleCompilationTest.java
+++ b/compilationTests/src/test/java/android/databinding/compilationTest/SimpleCompilationTest.java
@@ -20,13 +20,21 @@ package android.databinding.compilationTest;
 import org.apache.commons.lang3.StringUtils;
 import org.junit.Test;
 
+import android.databinding.tool.processing.ErrorMessages;
+import android.databinding.tool.processing.ScopedErrorReport;
+import android.databinding.tool.processing.ScopedException;
+import android.databinding.tool.store.Location;
+
 import java.io.File;
 import java.io.IOException;
 import java.net.URISyntaxException;
+import java.util.List;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 public class SimpleCompilationTest extends BaseCompilationTest {
 
@@ -50,17 +58,95 @@ public class SimpleCompilationTest extends BaseCompilationTest {
                 result.resultContainsText("BUILD SUCCESSFUL"));
     }
 
+    private ScopedException singleFileErrorTest(String resource, String targetFile,
+            String expectedExtract, String errorMessage)
+            throws IOException, URISyntaxException, InterruptedException {
+        prepareProject();
+        copyResourceTo(resource, targetFile);
+        CompilationResult result = runGradle("assembleDebug");
+        assertNotEquals(0, result.resultCode);
+        ScopedException scopedException = result.getBindingException();
+        assertNotNull(scopedException);
+        ScopedErrorReport report = scopedException.getScopedErrorReport();
+        assertNotNull(report);
+        assertEquals(1, report.getLocations().size());
+        Location loc = report.getLocations().get(0);
+        if (expectedExtract != null) {
+            String extract = extract(targetFile, loc);
+            assertEquals(expectedExtract, extract);
+        }
+        final File errorFile = new File(report.getFilePath());
+        assertTrue(errorFile.exists());
+        assertEquals(new File(testFolder, targetFile).getCanonicalFile(),
+                errorFile.getCanonicalFile());
+        if (errorMessage != null) {
+            assertEquals(errorMessage, scopedException.getBareMessage());
+        }
+        return scopedException;
+    }
+
     @Test
-    public void testUndefinedVariable() throws IOException, URISyntaxException,
-            InterruptedException {
+    public void testMultipleExceptionsInDifferentFiles()
+            throws IOException, URISyntaxException, InterruptedException {
         prepareProject();
         copyResourceTo("/layout/undefined_variable_binding.xml",
                 "/app/src/main/res/layout/broken.xml");
+        copyResourceTo("/layout/invalid_setter_binding.xml",
+                "/app/src/main/res/layout/invalid_setter.xml");
         CompilationResult result = runGradle("assembleDebug");
         assertNotEquals(0, result.resultCode);
-        assertTrue("Undefined variable",
-                result.errorContainsText(
-                        "Identifiers must have user defined types from the XML file. myVariable is missing it"));
+        List<ScopedException> bindingExceptions = result.getBindingExceptions();
+        assertEquals(2, bindingExceptions.size());
+        File broken = new File(testFolder, "/app/src/main/res/layout/broken.xml");
+        File invalidSetter = new File(testFolder, "/app/src/main/res/layout/invalid_setter.xml");
+        for (ScopedException exception : bindingExceptions) {
+            ScopedErrorReport report = exception.getScopedErrorReport();
+            final File errorFile = new File(report.getFilePath());
+            String message = null;
+            String expectedErrorFile = null;
+            if (errorFile.getCanonicalPath().equals(broken.getCanonicalPath())) {
+                message = String.format(ErrorMessages.UNDEFINED_VARIABLE, "myVariable");
+                expectedErrorFile = "/app/src/main/res/layout/broken.xml";
+            } else if (errorFile.getCanonicalPath().equals(invalidSetter.getCanonicalPath())) {
+                message = String.format(ErrorMessages.CANNOT_FIND_SETTER_CALL, "android:textx",
+                        String.class.getCanonicalName());
+                expectedErrorFile = "/app/src/main/res/layout/invalid_setter.xml";
+            } else {
+                fail("unexpected exception " + exception.getBareMessage());
+            }
+            assertEquals(1, report.getLocations().size());
+            Location loc = report.getLocations().get(0);
+            String extract = extract(expectedErrorFile, loc);
+            assertEquals("myVariable", extract);
+            assertEquals(message, exception.getBareMessage());
+        }
+    }
+
+    @Test
+    public void testUndefinedVariable() throws IOException, URISyntaxException,
+            InterruptedException {
+        ScopedException ex = singleFileErrorTest("/layout/undefined_variable_binding.xml",
+                "/app/src/main/res/layout/broken.xml", "myVariable",
+                String.format(ErrorMessages.UNDEFINED_VARIABLE, "myVariable"));
+    }
+
+    @Test
+    public void testInvalidSetterBinding() throws IOException, URISyntaxException,
+            InterruptedException {
+        prepareProject();
+        ScopedException ex = singleFileErrorTest("/layout/invalid_setter_binding.xml",
+                "/app/src/main/res/layout/invalid_setter.xml", "myVariable",
+                String.format(ErrorMessages.CANNOT_FIND_SETTER_CALL, "android:textx",
+                        String.class.getCanonicalName()));
+    }
+
+    @Test
+    public void testInvalidVariableType() throws IOException, URISyntaxException,
+            InterruptedException {
+        prepareProject();
+        ScopedException ex = singleFileErrorTest("/layout/invalid_variable_type.xml",
+                "/app/src/main/res/layout/invalid_variable.xml", "myVariable",
+                String.format(ErrorMessages.CANNOT_RESOLVE_TYPE, "myVariable~"));
     }
 
     @Test
@@ -96,8 +182,17 @@ public class SimpleCompilationTest extends BaseCompilationTest {
         copyResourceTo("/layout/merge_include.xml", "/app/src/main/res/layout/merge_include.xml");
         CompilationResult result = runGradle("assembleDebug");
         assertNotEquals(0, result.resultCode);
-        assertTrue("Merge shouldn't support includes as root. Error message was '" + result.error + "'",
-                result.errorContainsText(
-                        "Data binding does not support include elements as direct children of a merge element"));
+        List<ScopedException> errors = ScopedException.extractErrors(result.error);
+        assertEquals(result.error, 1, errors.size());
+        final ScopedException ex = errors.get(0);
+        final ScopedErrorReport report = ex.getScopedErrorReport();
+        final File errorFile = new File(report.getFilePath());
+        assertTrue(errorFile.exists());
+        assertEquals(
+                new File(testFolder, "/app/src/main/res/layout/merge_include.xml")
+                        .getCanonicalFile(),
+                errorFile.getCanonicalFile());
+        assertEquals("Merge shouldn't support includes as root. Error message was '" + result.error,
+                ErrorMessages.INCLUDE_INSIDE_MERGE, ex.getBareMessage());
     }
 }