fix: Fixes dependent source discovery

Parent directories for sources are now added to the compiler's source
path so any types referenced in them that are available in the same
directories can be found even when they are not explicitely mentioned
in any `//SOURCES` lines. This also fixes the problem where adding a
`//DEPS` line would cause the compiler to be unable to find those same
types.

Fixes #1502

Author: quintesse

itests/extending/Bar.java

@@ -0,0 +1,3 @@
+package extending;
+
+public class Bar {}

itests/extending/Foo.java

@@ -0,0 +1,10 @@
+///usr/bin/env jbang "$0" "$@" ; exit $?
+///DEPS com.github.lalyos:jfiglet:0.0.9
+
+package extending;
+
+public class Foo extends Bar {
+    public static void main(String... args) {
+        System.out.println("hello JBang");
+    }
+}

src/main/java/dev/jbang/dependencies/ModularClassPath.java

@@ -50,12 +50,16 @@ public List<String> getClassPaths() {
 
 	public String getClassPath() {
 		if (classPath == null) {
-			classPath = String.join(CP_SEPARATOR, getClassPaths());
+			classPath = toClassPath(getClassPaths());
 		}
 
 		return classPath;
 	}
 
+	public static String toClassPath(List<String> pathElements) {
+		return String.join(CP_SEPARATOR, pathElements);
+	}
+
 	public String getManifestPath() {
 		if (manifestPath == null) {
 			manifestPath = artifacts.stream()

src/main/java/dev/jbang/source/ResourceRef.java

@@ -35,6 +35,10 @@ public boolean isStdin() {
 		return originalResource != null && isStdin(originalResource);
 	}
 
+	public boolean isFile() {
+		return originalResource != null && Util.isValidPath(originalResource);
+	}
+
 	@Nullable
 	public Path getFile() {
 		return file;

src/main/java/dev/jbang/source/Source.java

@@ -1,13 +1,16 @@
 package dev.jbang.source;
 
+import java.nio.file.Path;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 
 import dev.jbang.cli.BaseCommand;
 import dev.jbang.cli.ExitException;
@@ -87,6 +90,29 @@ public ResourceRef getResourceRef() {
 		return resourceRef;
 	}
 
+	@Nullable
+	public ResourceRef getSourceDirRef() {
+		if (contents != null && resourceRef.isFile()) {
+			Path parent = getResourceRef().getFile().getParent();
+			Optional<String> pkg = getJavaPackage();
+			if (pkg.isPresent()) {
+				String[] elems = pkg.get().split("\\.");
+				Collections.reverse(Arrays.asList(elems));
+				for (String elem : elems) {
+					if (parent != null && !elem.equals(parent.getFileName().toString())) {
+						// if path doesn't match package we return null
+						return null;
+					}
+					parent = parent.getParent();
+				}
+			}
+			return ResourceRef.forFile(parent);
+		} else {
+			// If the resource isn't a local file we return null
+			return null;
+		}
+	}
+
 	public Optional<String> getJavaPackage() {
 		if (contents != null) {
 			return Util.getSourcePackage(contents);
@@ -145,6 +171,10 @@ public Project updateProject(Project prj, ResourceResolver resolver) {
 		if (!prj.getMainSourceSet().getSources().contains(getResourceRef())) {
 			SourceSet ss = prj.getMainSourceSet();
 			ss.addSource(this.getResourceRef());
+			ResourceRef srcDir = getSourceDirRef();
+			if (srcDir != null) {
+				ss.addSourceDir(srcDir);
+			}
 			ss.addResources(tagReader.collectFiles(resourceRef,
 					new SiblingResourceResolver(resourceRef, ResourceResolver.forResources())));
 			ss.addDependencies(collectDependencies());

src/main/java/dev/jbang/source/SourceSet.java

@@ -4,7 +4,9 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Stream;
 
 import javax.annotation.Nonnull;
@@ -21,6 +23,7 @@
 public class SourceSet {
 	private final List<ResourceRef> sources = new ArrayList<>();
 	private final List<RefTarget> resources = new ArrayList<>();
+	private final Set<ResourceRef> sourceDirs = new HashSet<>();
 	private final List<String> dependencies = new ArrayList<>();
 	private final List<String> classPaths = new ArrayList<>();
 	private final List<String> compileOptions = new ArrayList<>();
@@ -67,6 +70,23 @@ public SourceSet addResources(Collection<RefTarget> resources) {
 		return this;
 	}
 
+	@Nonnull
+	public Set<ResourceRef> getSourceDirs() {
+		return Collections.unmodifiableSet(sourceDirs);
+	}
+
+	@Nonnull
+	public SourceSet addSourceDir(ResourceRef sourceDir) {
+		sourceDirs.add(sourceDir);
+		return this;
+	}
+
+	@Nonnull
+	public SourceSet addSourceDirs(Collection<ResourceRef> sourceDirs) {
+		this.sourceDirs.addAll(sourceDirs);
+		return this;
+	}
+
 	@Nonnull
 	public List<String> getDependencies() {
 		return Collections.unmodifiableList(dependencies);

src/main/java/dev/jbang/source/buildsteps/CompileBuildStep.java

@@ -10,6 +10,7 @@
 
 import dev.jbang.cli.ExitException;
 import dev.jbang.dependencies.MavenCoordinate;
+import dev.jbang.dependencies.ModularClassPath;
 import dev.jbang.source.Builder;
 import dev.jbang.source.Project;
 import dev.jbang.util.CommandBuffer;
@@ -42,10 +43,22 @@ protected Project compile() throws IOException {
 		optionList.addAll(project.getMainSourceSet().getCompileOptions());
 		String path = project.resolveClassPath().getClassPath();
 		if (!Util.isBlankString(path)) {
-			optionList.addAll(Arrays.asList("-classpath", path));
+			optionList.add("-classpath");
+			optionList.add(path);
 		}
 		optionList.addAll(Arrays.asList("-d", compileDir.toAbsolutePath().toString()));
 
+		// add -sourcepath for all source folders
+		List<String> srcDirs = project	.getMainSourceSet()
+										.getSourceDirs()
+										.stream()
+										.map(d -> d.getFile().toString())
+										.collect(Collectors.toList());
+		if (!srcDirs.isEmpty()) {
+			optionList.add("-sourcepath");
+			optionList.add(ModularClassPath.toClassPath(srcDirs));
+		}
+
 		// add source files to compile
 		optionList.addAll(project	.getMainSourceSet()
 									.getSources()

src/main/java/dev/jbang/source/generators/JshCmdGenerator.java

@@ -12,6 +12,7 @@
 
 import org.apache.commons.text.StringEscapeUtils;
 
+import dev.jbang.dependencies.ModularClassPath;
 import dev.jbang.source.*;
 import dev.jbang.util.JavaUtil;
 import dev.jbang.util.Util;
@@ -98,6 +99,17 @@ protected List<String> generateCommandLineList() throws IOException {
 		fullArgs.addAll(optionalArgs);
 
 		if (project.isJShell()) {
+			// add -sourcepath for all source folders
+			List<String> srcDirs = project	.getMainSourceSet()
+											.getSourceDirs()
+											.stream()
+											.map(d -> d.getFile().toString())
+											.collect(Collectors.toList());
+			if (!srcDirs.isEmpty()) {
+				fullArgs.add("-C-sourcepath");
+				fullArgs.add(ModularClassPath.toClassPath(srcDirs));
+			}
+
 			ArrayList<ResourceRef> revSources = new ArrayList<>(project.getMainSourceSet().getSources());
 			Collections.reverse(revSources);
 			for (ResourceRef s : revSources) {

src/test/java/dev/jbang/source/TestBuilder.java

@@ -204,6 +204,7 @@ void testAdditionalSourcesFolder() throws IOException {
 		Util.setCwd(examplesTestFolder);
 		String mainFile = examplesTestFolder.resolve("foo.java").toString();
 		String incFile = examplesTestFolder.resolve("bar/Bar.java").toString();
+		String srcPath = examplesTestFolder.resolve("bar") + File.pathSeparator + examplesTestFolder;
 
 		ProjectBuilder pb = ProjectBuilder.create();
 		pb.additionalSources(Arrays.asList("bar"));
@@ -217,6 +218,7 @@ protected Builder<Project> getCompileBuildStep() {
 					protected void runCompiler(List<String> optionList) {
 						assertThat(optionList, hasItem(mainFile));
 						assertThat(optionList, hasItem(incFile));
+						assertThat(optionList, hasItems("-sourcepath", srcPath));
 						// Skip the compiler
 					}
 				};
@@ -490,4 +492,24 @@ protected void runNativeBuilder(List<String> optionList) throws IOException {
 			}
 		}.setFresh(true).build();
 	}
+
+	@Test
+	void testMultiSourceWithDeps() throws IOException {
+		Path foo = examplesTestFolder.resolve("extending").resolve("Foo.java");
+		ProjectBuilder pb = ProjectBuilder.create();
+		Project prj = pb.build(foo.toString());
+
+		new JavaSource.JavaAppBuilder(prj) {
+			@Override
+			protected Builder<Project> getCompileBuildStep() {
+				return new JavaCompileBuildStep() {
+					@Override
+					protected void runCompiler(List<String> optionList) {
+						assertThat(optionList, hasItems("-sourcepath", examplesTestFolder.toString(), foo.toString()));
+						// Skip the compiler
+					}
+				};
+			}
+		}.setFresh(true).build();
+	}
 }