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respect iterator return value of Infinity/-Infinity in _.min/_.max #1606

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Merged
merged 1 commit into from
Apr 28, 2014
Merged

respect iterator return value of Infinity/-Infinity in _.min/_.max #1606

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10 changes: 10 additions & 0 deletions test/collections.js
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Original file line number Diff line number Diff line change
Expand Up @@ -301,6 +301,11 @@

equal(3, _.max([1, 2, 3, 'test']), 'Finds correct max in array starting with num and containing a NaN');
equal(3, _.max(['test', 1, 2, 3]), 'Finds correct max in array starting with NaN');

var a = {x: -Infinity};
var b = {x: -Infinity};
var iterator = function(o){ return o.x; };
equal(_.max([a, b], iterator), a, 'Respects iterator return value of -Infinity');
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This test ensures that the first element in the list is returned.

});

test('min', function() {
Expand All @@ -321,6 +326,11 @@

equal(1, _.min([1, 2, 3, 'test']), 'Finds correct min in array starting with num and containing a NaN');
equal(1, _.min(['test', 1, 2, 3]), 'Finds correct min in array starting with NaN');

var a = {x: Infinity};
var b = {x: Infinity};
var iterator = function(o){ return o.x; };
equal(_.min([a, b], iterator), a, 'Respects iterator return value of Infinity');
});

test('sortBy', function() {
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4 changes: 2 additions & 2 deletions underscore.js
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Expand Up @@ -232,7 +232,7 @@
} else {
_.each(obj, function(value, index, list) {
computed = iterator ? iterator.call(context, value, index, list) : value;
if (computed > lastComputed) {
if (computed > lastComputed || (computed === -Infinity && result === -Infinity)) {
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The result === -Infinity check ensures we return the first value for which the iterator returns -Infinity should the iterator return -Infinity for every value.

result = value;
lastComputed = computed;
}
Expand All @@ -255,7 +255,7 @@
} else {
_.each(obj, function(value, index, list) {
computed = iterator ? iterator.call(context, value, index, list) : value;
if (computed < lastComputed) {
if (computed < lastComputed || (computed === Infinity && result === Infinity)) {
result = value;
lastComputed = computed;
}
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