Print exit code along with process failures

Author: Jonathing

src/main/java/net/minecraftforge/mcmaven/impl/mappings/Mappings.java

@@ -219,7 +219,7 @@ private File getMappings(MCPSide side, Task srgMappings, Task clientTask, Task s
 
         var ret = ProcessUtils.runJar(jdk, log.getParentFile(), log, tool, Collections.emptyList(), args);
         if (ret.exitCode != 0)
-            throw new IllegalStateException("Failed to run MCP Step, See log: " + log.getAbsolutePath());
+            throw new IllegalStateException("Failed to run MCP Step (exit code " + ret.exitCode + "), See log: " + log.getAbsolutePath());
 
         cache.save();
         return output;

src/main/java/net/minecraftforge/mcmaven/impl/repo/forge/Patcher.java

@@ -437,7 +437,7 @@ public static File modifyAccess(File globalBase, Task inputTask, File cfg, Cache
 
         var ret = ProcessUtils.runJar(jdk, globalBase, log, tool, Collections.emptyList(), args);
         if (ret.exitCode != 0)
-            throw new IllegalStateException("Failed to run Access Transformer, See log: " + log.getAbsolutePath());
+            throw new IllegalStateException("Failed to run Access Transformer (exit code " + ret.exitCode + "), See log: " + log.getAbsolutePath());
 
         cache.save();
         return output;
@@ -476,7 +476,7 @@ public static File stripSides(File globalBase, Task inputTask, File cfg, Cache d
 
         var ret = ProcessUtils.runJar(jdk, globalBase, log, tool, Collections.emptyList(), args);
         if (ret.exitCode != 0)
-            throw new IllegalStateException("Failed to run Side Stripper, See log: " + log.getAbsolutePath());
+            throw new IllegalStateException("Failed to run Side Stripper (exit code " + ret.exitCode + "), See log: " + log.getAbsolutePath());
 
         cache.save();
         return output;
@@ -550,7 +550,7 @@ private File postProcess(Task inputTask, PatcherConfig.V2.DataFunction data, Fil
 
         var ret = ProcessUtils.runJar(jdk, log.getParentFile(), log, tool, data.getJvmArgs(), args);
         if (ret.exitCode != 0)
-            throw new IllegalStateException("Failed to run MCP Step, See log: " + log.getAbsolutePath());
+            throw new IllegalStateException("Failed to run MCP Step (exit code " + ret.exitCode + "), See log: " + log.getAbsolutePath());
 
         cache.save();
         return output;

src/main/java/net/minecraftforge/mcmaven/impl/repo/mcpconfig/MCPTaskFactory.java

@@ -863,7 +863,7 @@ private File execute(List<TaskOrArg> jvmArgs, List<TaskOrArg> runArgs, MCPConfig
 
         var ret = ProcessUtils.runJar(jdk, log.getParentFile(), log, tool, jvm, run);
         if (ret.exitCode != 0)
-            throw new IllegalStateException("Failed to run MCP Step, See log: " + log.getAbsolutePath());
+            throw new IllegalStateException("Failed to run MCP Step (exit code " + ret.exitCode + "), See log: " + log.getAbsolutePath());
 
         cache.save();
         return output;

src/main/java/net/minecraftforge/mcmaven/impl/util/ProcessUtils.java

@@ -146,7 +146,10 @@ public static int runCommand(File workDir, Consumer<String> lines, String... arg
             }
         }
 
-        return process.exitValue();
+        var exitValue = process.exitValue();
+        if (exitValue != 0)
+            lines.accept("Process returned non-zero exit value: " + exitValue);
+        return exitValue;
     }
 
     static Path getPathFromResource(String resource) {