diff --git a/parser/parser.test.ts b/parser/parser.test.ts
index f344129..b908f34 100644
--- a/parser/parser.test.ts
+++ b/parser/parser.test.ts
@@ -10,7 +10,7 @@ import {
   Percentage,
   Unary,
   Value,
-  Variable
+  Variable,
 } from '../nodes'
 import {lex, Token} from './lex'
 import {parse} from './parser'
@@ -47,15 +47,15 @@ function cur(s: string): Currency {
 let cases: [string, Node, Varname[]?][] = [
   [
     '',
-    new Nil()
+    new Nil(),
   ],
   [
     '1 + 2',
-    new Binary(op('+'), new Value(n(1)), new Value(n(2)))
+    new Binary(op('+'), new Value(n(1)), new Value(n(2))),
   ],
   [
     '1 + - 2',
-    new Binary(op('+'), new Value(n(1)), new Unary(op('-'), new Value(n(2))))
+    new Binary(op('+'), new Value(n(1)), new Unary(op('-'), new Value(n(2)))),
   ],
   [
     '1-2+3',
@@ -63,7 +63,7 @@ let cases: [string, Node, Varname[]?][] = [
       new Binary(op('-'),
         new Value(n(1)),
         new Value(n(2))),
-      new Value(n(3)))
+      new Value(n(3))),
   ],
   [
     '1+2*3',
@@ -71,7 +71,7 @@ let cases: [string, Node, Varname[]?][] = [
       new Value(n(1)),
       new Binary(op('*'),
         new Value(n(2)),
-        new Value(n(3))))
+        new Value(n(3)))),
   ],
   [
     '1/2+3*4',
@@ -81,7 +81,7 @@ let cases: [string, Node, Varname[]?][] = [
         new Value(n(2))),
       new Binary(op('*'),
         new Value(n(3)),
-        new Value(n(4))))
+        new Value(n(4)))),
   ],
   [
     '(1+2)*3',
@@ -89,19 +89,23 @@ let cases: [string, Node, Varname[]?][] = [
       new Binary(op('+'),
         new Value(n(1)),
         new Value(n(2))),
-      new Value(n(3)))
+      new Value(n(3))),
   ],
   [
     '0.05',
-    new Value(n(0.05))
+    new Value(n(0.05)),
   ],
   [
     '-+0',
-    new Unary(op('-'), new Unary(op('+'), new Value(n(0))))
+    new Unary(op('-'), new Unary(op('+'), new Value(n(0)))),
+  ],
+  [
+    'some-thing is -5',
+    new Unary(op('-'), new Unary(op('-'), new Value(n(5)))),
   ],
   [
     '1 % 2%',
-    new Binary(op('%'), new Value(n(1)), new Percentage(p('2%')))
+    new Binary(op('%'), new Value(n(1)), new Percentage(p('2%'))),
   ],
   [
     '(1 - ',
@@ -121,31 +125,31 @@ let cases: [string, Node, Varname[]?][] = [
   ],
   [
     '1 % ƒы2',
-    new Binary(op('%'), new Value(n(1)), new Variable(v('ƒы2')))
+    new Binary(op('%'), new Value(n(1)), new Variable(v('ƒы2'))),
   ],
   [
     '1 ^ 2',
-    new Binary(op('^'), new Value(n(1)), new Value(n(2)))
+    new Binary(op('^'), new Value(n(1)), new Value(n(2))),
   ],
   [
     '1usd',
-    new Value(n(1), cur('usd'))
+    new Value(n(1), cur('usd')),
   ],
   [
     '1 usd',
-    new Value(n(1), cur('usd'))
+    new Value(n(1), cur('usd')),
   ],
   [
     'USD 1',
-    new Value(n(1), cur('USD'))
+    new Value(n(1), cur('USD')),
   ],
   [
     '$1',
-    new Value(n(1), cur('$'))
+    new Value(n(1), cur('$')),
   ],
   [
     '1$',
-    new Value(n(1), cur('$'))
+    new Value(n(1), cur('$')),
   ],
   [
     '1 usd in rub',
@@ -165,7 +169,7 @@ let cases: [string, Node, Varname[]?][] = [
   ],
   [
     '7% of $1k 2019',
-    new Fraction(op('of'), new Percentage(p('7%')), new Value(n('1k'), cur('$')))
+    new Fraction(op('of'), new Percentage(p('7%')), new Value(n('1k'), cur('$'))),
   ],
   [
     '1 btc in usd / 10 users',
@@ -173,7 +177,7 @@ let cases: [string, Node, Varname[]?][] = [
       new Conversion(op('in'),
         new Value(n('1'), cur('btc')),
         cur('usd')),
-      new Value(n('10')))
+      new Value(n('10'))),
   ],
   [
     '1 + 1 btc in usd x 10 users',
@@ -183,11 +187,11 @@ let cases: [string, Node, Varname[]?][] = [
           new Value(n('1')),
           new Value(n('1'), cur('btc'))),
         cur('usd')),
-      new Value(n('10')))
+      new Value(n('10'))),
   ],
   [
     '2×2',
-    new Binary(op('×'), new Value(n(2)), new Value(n(2)))
+    new Binary(op('×'), new Value(n(2)), new Value(n(2))),
   ],
   [
     'var = 1',
@@ -197,27 +201,27 @@ let cases: [string, Node, Varname[]?][] = [
   ],
   [
     'Yearly price = 10k',
-    new Assignment(op('='), v('Yearly price'), new Value(n('10k')))
+    new Assignment(op('='), v('Yearly price'), new Value(n('10k'))),
   ],
   [
     'soft_limit = 100M',
-    new Assignment(op('='), v('soft_limit'), new Value(n('100M')))
+    new Assignment(op('='), v('soft_limit'), new Value(n('100M'))),
   ],
   [
     'a b + a b c',
     new Binary(op('+'),
       new Variable(v('a b')),
       new Variable(v('a b c'))),
-    ['a b' as Varname, 'a b c' as Varname]
+    ['a b' as Varname, 'a b c' as Varname],
   ],
 ]
 
 for (let [expr, ast, vars] of cases) {
   test('parse ' + expr, t => {
-    let [node,] = parse(lex(expr, vars))
+    let [node] = parse(lex(expr, vars))
     t.is(
       JSON.stringify(node, replacer, 4),
-      JSON.stringify(ast, replacer, 4)
+      JSON.stringify(ast, replacer, 4),
     )
   })
 }