37 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			37 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }
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| 
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| import { print } from "@webassemblyjs/wast-printer";
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| var SHOW_LINES_AROUND_POINTER = 5;
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| 
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| function repeat(char, nb) {
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|   return Array(nb).fill(char).join("");
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| } // TODO(sven): allow arbitrary ast nodes
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| 
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| 
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| export function codeFrameFromAst(ast, loc) {
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|   return codeFrameFromSource(print(ast), loc);
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| }
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| export function codeFrameFromSource(source, loc) {
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|   var start = loc.start,
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|       end = loc.end;
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|   var length = 1;
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| 
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|   if (_typeof(end) === "object") {
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|     length = end.column - start.column + 1;
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|   }
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| 
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|   return source.split("\n").reduce(function (acc, line, lineNbr) {
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|     if (Math.abs(start.line - lineNbr) < SHOW_LINES_AROUND_POINTER) {
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|       acc += line + "\n";
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|     } // Add a new line with the pointer padded left
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| 
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| 
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|     if (lineNbr === start.line - 1) {
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|       acc += repeat(" ", start.column - 1);
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|       acc += repeat("^", length);
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|       acc += "\n";
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|     }
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| 
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|     return acc;
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|   }, "");
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| } | 
