added stepUnmappedLines option and disabled stepping through lua in sourcemapped files by default

Author: tomblind

README.md

@@ -113,6 +113,10 @@ A list of [Lua patterns](https://www.lua.org/manual/5.4/manual.html#6.4.1) that
 
 Example: `ignorePatterns: ["^/usr"]`
 
+#### `stepUnmappedLines`
+
+Step into Lua when stepping through source-mapped code and no mapping is available for the current line.
+
 #### `breakInCoroutines`
 
 Break into the debugger when errors occur inside coroutines.

debugger/debugger.ts

@@ -815,6 +815,8 @@ export namespace Debugger {
 
     const debugHookStackOffset = 2;
     const breakpointLookup = Breakpoint.getLookup();
+    const stepUnmappedLinesEnv: LuaDebug.StepUnmappedLinesEnv = "LOCAL_LUA_DEBUGGER_STEP_UNMAPPED_LINES";
+    const skipUnmappedLines = (os.getenv(stepUnmappedLinesEnv) !== "1");
 
     function debugHook(event: "call" | "return" | "tail return" | "count" | "line", line?: number) {
         //Stepping
@@ -849,8 +851,9 @@ export namespace Debugger {
                 }
 
                 //Ignore patterns
+                let source: string | undefined;
                 if (ignorePatterns) {
-                    const source = Path.format(topFrameSource.source);
+                    source = Path.format(topFrameSource.source);
                     for (const pattern of ignorePatterns) {
                         const [match] = source.match(pattern);
                         if (match) {
@@ -859,6 +862,16 @@ export namespace Debugger {
                     }
                 }
 
+                //Ignore un-mapped lines in files with source maps
+                if (skipUnmappedLines) {
+                    source ||= Path.format(topFrameSource.source);
+                    const sourceMap = SourceMap.get(source);
+                    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+                    if (sourceMap && !sourceMap.mappings[line!]) {
+                        return;
+                    }
+                }
+
                 Send.debugBreak("step", "step", getThreadId(activeThread));
                 if (debugBreak(activeThread, debugHookStackOffset, line)) {
                     return;

debugger/protocol.d.ts

@@ -113,6 +113,7 @@ declare namespace LuaDebug {
 
     type ScriptRootsEnv = "LOCAL_LUA_DEBUGGER_SCRIPT_ROOTS";
     type BreakInCoroutinesEnv = "LOCAL_LUA_DEBUGGER_BREAK_IN_COROUTINES";
+    type StepUnmappedLinesEnv = "LOCAL_LUA_DEBUGGER_STEP_UNMAPPED_LINES";
     type InputFileEnv = "LOCAL_LUA_DEBUGGER_INPUT_FILE";
     type OutputFileEnv = "LOCAL_LUA_DEBUGGER_OUTPUT_FILE";
 }

extension/launchConfig.ts

@@ -42,6 +42,7 @@ export interface LaunchConfig {
     verbose?: boolean;
     stopOnEntry?: boolean;
     breakInCoroutines?: boolean;
+    stepUnmappedLines?: boolean;
     scriptFiles?: string[];
     ignorePatterns?: string[];
 }

extension/luaDebugSession.ts

@@ -72,6 +72,7 @@ const envVariable = "LOCAL_LUA_DEBUGGER_VSCODE";
 const filePathEnvVariable = "LOCAL_LUA_DEBUGGER_FILEPATH";
 const scriptRootsEnvVariable: LuaDebug.ScriptRootsEnv = "LOCAL_LUA_DEBUGGER_SCRIPT_ROOTS";
 const breakInCoroutinesEnv: LuaDebug.BreakInCoroutinesEnv = "LOCAL_LUA_DEBUGGER_BREAK_IN_COROUTINES";
+const stepUnmappedLinesEnv: LuaDebug.StepUnmappedLinesEnv = "LOCAL_LUA_DEBUGGER_STEP_UNMAPPED_LINES";
 const inputFileEnv: LuaDebug.InputFileEnv = "LOCAL_LUA_DEBUGGER_INPUT_FILE";
 const outputFileEnv: LuaDebug.OutputFileEnv = "LOCAL_LUA_DEBUGGER_OUTPUT_FILE";
 
@@ -232,6 +233,9 @@ export class LuaDebugSession extends LoggingDebugSession {
         if (typeof this.config.breakInCoroutines !== "undefined") {
             processOptions.env[breakInCoroutinesEnv] = this.config.breakInCoroutines ? "1" : "0";
         }
+        if (typeof this.config.stepUnmappedLines !== "undefined") {
+            processOptions.env[stepUnmappedLinesEnv] = this.config.stepUnmappedLines ? "1" : "0";
+        }
 
         //Open pipes
         if (this.config.program.communication === "pipe") {

package.json

@@ -131,6 +131,11 @@
                                 },
                                 "description": "Lua patterns specifying scripts to be ignored when stepping"
                             },
+                            "stepUnmappedLines": {
+                                "type": "boolean",
+                                "description": "Step into lua when stepping through unmapped lines in source-mapped files",
+                                "default": true
+                            },
                             "verbose": {
                                 "type": "boolean",
                                 "description": "Enable verbose output",