lib/coverage_apply.js
function countLine() {
		var ret;
        // skip first line
        if (isFirstLine) {
            isFirstLine = false;
            return ret;
        }
		if (this[0].start && analyzing.indexOf(this) < 0) {
			giveNameToAnonymousFunction.call(this);
			var lineId = this[0].start.line + lineOffset + ''; //this[0].name + ':' + this[0].start.line + ":" + this[0].start.pos;
			rememberStatement(lineId);

			analyzing.push(this);
			ret = [ "splice",
				[
					[ "stat",
						[ "call",
                            ["dot", ["name", "require"], "coverage_line"],
							[
								[ "string", moduleName],
								[ "string", lineId]
							]
						]
					],
					walker.walk(this)
				]
			];
			analyzing.pop(this);
		}
		return ret;
	}
function countLine() {
		var ret;
        // skip first line
        if (isFirstLine) {
            isFirstLine = false;
            return ret;
        }
		if (this[0].start && analyzing.indexOf(this) < 0) {
			giveNameToAnonymousFunction.call(this);
			var lineId = this[0].start.line + lineOffset + ''; //this[0].name + ':' + this[0].start.line + ":" + this[0].start.pos;
			rememberStatement(lineId);

			analyzing.push(this);
			ret = [ "splice",
				[
					[ "stat",
						[ "call",
                            ["dot", ["name", "require"], "coverage_line"],
							[
								[ "string", moduleName],
								[ "string", lineId]
							]
						]
					],
					walker.walk(this)
				]
			];
			analyzing.pop(this);
		}
		return ret;
	}
Generic function for counting a line.
It generates a lineId from the line number and the block name (in minified files there
are more logical lines on the same file line) and adds a function call before the actual
line of code.

'this' is any node in the AST