refactor: Move list into CallFrame

Author: Jan Krems

lib/internal/inspect-repl.js

@@ -312,6 +312,49 @@ function createRepl(inspector) {
     }
   }
 
+  class SourceSnippet {
+    constructor(location, delta, scriptSource) {
+      Object.assign(this, location);
+      this.scriptSource = scriptSource;
+      this.delta = delta;
+    }
+
+    toString() {
+      return this[util.inspect.custom]();
+    }
+
+    [util.inspect.custom]() {
+      const { scriptId, lineNumber, columnNumber, delta, scriptSource } = this;
+      const start = Math.max(1, lineNumber - delta + 1);
+      const end = lineNumber + delta + 1;
+
+      const lines = scriptSource.split('\n');
+      return lines.slice(start - 1, end).map((lineText, offset) => {
+        const i = start + offset;
+        const isCurrent = i === (lineNumber + 1);
+
+        const markedLine = isCurrent
+          ? markSourceColumn(lineText, columnNumber, inspector.repl)
+          : lineText;
+
+        let isBreakpoint = false;
+        knownBreakpoints.forEach(({ location }) => {
+          if (location && location.scriptId === scriptId && (location.lineNumber + 1) === i) {
+            isBreakpoint = true;
+          }
+        });
+
+        let prefixChar = ' ';
+        if (isCurrent) {
+          prefixChar = '>';
+        } else if (isBreakpoint) {
+          prefixChar = '*';
+        }
+        return `${leftPad(i, prefixChar, end)} ${markedLine}`;
+      }).join('\n');
+    }
+  }
+
   class CallFrame {
     constructor(callFrame) {
       Object.assign(this, callFrame);
@@ -330,6 +373,12 @@ function createRepl(inspector) {
           })
       );
     }
+
+    list(delta = 5) {
+      const { scriptId } = this.location;
+      return Debugger.getScriptSource({ scriptId })
+        .then(({ scriptSource }) => new SourceSnippet(this.location, delta, scriptSource));
+    }
   }
 
   class Backtrace extends Array {
@@ -460,43 +509,9 @@ function createRepl(inspector) {
     return formatWatchers(verbose).then(print);
   }
 
-  function formatSourceContext(delta = 5) {
-    const { scriptId, lineNumber, columnNumber } = getCurrentLocation();
-    const start = Math.max(1, lineNumber - delta + 1);
-    const end = lineNumber + delta + 1;
-
-    return Debugger.getScriptSource({ scriptId })
-      .then(({ scriptSource }) => {
-        const lines = scriptSource.split('\n');
-        return lines.slice(start - 1, end).map((lineText, offset) => {
-          const i = start + offset;
-          const isCurrent = i === (lineNumber + 1);
-
-          const markedLine = isCurrent
-            ? markSourceColumn(lineText, columnNumber, inspector.repl)
-            : lineText;
-
-          let isBreakpoint = false;
-          knownBreakpoints.forEach(({ location }) => {
-            if (location && location.scriptId === scriptId && (location.lineNumber + 1) === i) {
-              isBreakpoint = true;
-            }
-          });
-
-          let prefixChar = ' ';
-          if (isCurrent) {
-            prefixChar = '>';
-          } else if (isBreakpoint) {
-            prefixChar = '*';
-          }
-          return `${leftPad(i, prefixChar, end)} ${markedLine}`;
-        }).join('\n');
-      });
-  }
-
   // List source code
   function list(delta = 5) {
-    return formatSourceContext(delta)
+    return selectedFrame.list(delta)
       .then(print, (error) => {
         print('You can\'t list source code right now');
         throw error;
@@ -684,7 +699,7 @@ function createRepl(inspector) {
     print(`${reason === 'other' ? 'break' : reason} in ${scriptUrl}:${lineNumber + 1}`);
 
     inspector.suspendReplWhile(() =>
-      Promise.all([formatWatchers(true), formatSourceContext(2)])
+      Promise.all([formatWatchers(true), selectedFrame.list(2)])
         .then(([watcherList, context]) => (watcherList ? `${watcherList}\n${context}` : context))
         .then(print));
   });