From 154bf7abd918177613c31b9db395e4f6ea1f28d1 Mon Sep 17 00:00:00 2001
From: Ivan Hetman <Ihromant@users.noreply.github.com>
Date: Tue, 19 Sep 2023 14:21:32 +0300
Subject: [PATCH] classlib: more fixes to Math.nextUp/nextDown (#746)

---
 .../main/java/org/teavm/classlib/java/lang/TMath.java  | 10 ++++++++--
 .../java/org/teavm/classlib/java/lang/MathTest.java    |  4 ++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/classlib/src/main/java/org/teavm/classlib/java/lang/TMath.java b/classlib/src/main/java/org/teavm/classlib/java/lang/TMath.java
index 09111543f..95c7b5977 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/lang/TMath.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/lang/TMath.java
@@ -387,6 +387,9 @@ public final class TMath extends TObject {
         if (TDouble.isNaN(d) || d == TDouble.POSITIVE_INFINITY) {
             return d;
         }
+        if (d == 0.0d) {
+            return Double.MIN_VALUE;
+        }
         long bits = TDouble.doubleToLongBits(d);
         if (d < 0) {
             bits--;
@@ -400,6 +403,9 @@ public final class TMath extends TObject {
         if (TFloat.isNaN(d) || d == TFloat.POSITIVE_INFINITY) {
             return d;
         }
+        if (d == 0) {
+            return Float.MIN_VALUE;
+        }
         int bits = TFloat.floatToIntBits(d);
         if (d < 0) {
             bits--;
@@ -417,7 +423,7 @@ public final class TMath extends TObject {
             return -Double.MIN_VALUE;
         }
         long bits = TDouble.doubleToLongBits(d);
-        if (d <= 0) {
+        if (d < 0) {
             bits++;
         } else {
             bits--;
@@ -433,7 +439,7 @@ public final class TMath extends TObject {
             return -Float.MIN_VALUE;
         }
         int bits = TFloat.floatToIntBits(d);
-        if (d <= 0) {
+        if (d < 0) {
             bits++;
         } else {
             bits--;
diff --git a/tests/src/test/java/org/teavm/classlib/java/lang/MathTest.java b/tests/src/test/java/org/teavm/classlib/java/lang/MathTest.java
index e2dcebdf4..0c15c914f 100644
--- a/tests/src/test/java/org/teavm/classlib/java/lang/MathTest.java
+++ b/tests/src/test/java/org/teavm/classlib/java/lang/MathTest.java
@@ -106,8 +106,12 @@ public class MathTest {
     public void nextWorks() {
         assertEquals(Double.valueOf(-Double.MIN_VALUE), Double.valueOf(Math.nextDown(0.0)));
         assertEquals(Double.valueOf(Double.MIN_VALUE), Double.valueOf(Math.nextUp(0.0)));
+        assertEquals(Double.valueOf(-Double.MIN_VALUE), Double.valueOf(Math.nextDown(-0.0)));
+        assertEquals(Double.valueOf(Double.MIN_VALUE), Double.valueOf(Math.nextUp(-0.0)));
         assertEquals(Float.valueOf(-Float.MIN_VALUE), Float.valueOf(Math.nextDown(0.0f)));
         assertEquals(Float.valueOf(Float.MIN_VALUE), Float.valueOf(Math.nextUp(0.0f)));
+        assertEquals(Float.valueOf(-Float.MIN_VALUE), Float.valueOf(Math.nextDown(-0.0f)));
+        assertEquals(Float.valueOf(Float.MIN_VALUE), Float.valueOf(Math.nextUp(-0.0f)));
         assertEquals(Double.valueOf(0.10000000000000002), Double.valueOf(Math.nextUp(0.1)));
         assertEquals(Double.valueOf(0.9999999999999999), Double.valueOf(Math.nextDown(1.0)));
         assertEquals(Double.valueOf(-0.09999999999999999), Double.valueOf(Math.nextUp(-0.1)));