From 6ffd604e1cf5874327dc628181c2394429d88d3c Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Tue, 4 May 2021 01:12:03 +0800
Subject: [PATCH] Chore: Improve readability of `Program` position fix part
 (#493)

---
 lib/espree.js | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/lib/espree.js b/lib/espree.js
index 757b6b10..2e6aec67 100644
--- a/lib/espree.js
+++ b/lib/espree.js
@@ -159,17 +159,27 @@ export default () => Parser => {
              * whitespace or leading comments). Acorn also counts trailing whitespace
              * as part of the program whereas Esprima only counts up to the last token.
              */
-            if (program.range) {
-                program.range[0] = program.body.length ? program.body[0].range[0] : program.range[0];
-                program.range[1] = extra.lastToken ? extra.lastToken.range[1] : program.range[1];
+            if (program.body.length) {
+                const [firstNode] = program.body;
+
+                if (program.range) {
+                    program.range[0] = firstNode.range[0];
+                }
+                if (program.loc) {
+                    program.loc.start = firstNode.loc.start;
+                }
+                program.start = firstNode.start;
             }
-            if (program.loc) {
-                program.loc.start = program.body.length ? program.body[0].loc.start : program.loc.start;
-                program.loc.end = extra.lastToken ? extra.lastToken.loc.end : program.loc.end;
+            if (extra.lastToken) {
+                if (program.range) {
+                    program.range[1] = extra.lastToken.range[1];
+                }
+                if (program.loc) {
+                    program.loc.end = extra.lastToken.loc.end;
+                }
+                program.end = extra.lastToken.end;
             }
 
-            program.start = program.body.length ? program.body[0].start : program.start;
-            program.end = extra.lastToken ? extra.lastToken.end : program.end;
 
             /*
              * https://github.com/eslint/espree/issues/349