From 60b1a085c7c0cdb6c1ad2834019ac5206d3d771a Mon Sep 17 00:00:00 2001
From: emv <emv@opencascade.com>
Date: Fri, 21 Sep 2018 16:22:37 +0300
Subject: [PATCH] 0030154: [REGRESSION] Modeling Algorithms - Boolean Operation
 on planar geometry hangs inside BRepLib::FindValidRange()

Do not allow the precision with which the valid range is found to be less than the epsilon of the max parameter of the edge's range.
Test cases for the issue.
---
 src/BRepLib/BRepLib_1.cxx      |  6 ++++--
 tests/bugs/modalg_7/bug30154_1 | 15 +++++++++++++++
 tests/bugs/modalg_7/bug30154_2 | 23 +++++++++++++++++++++++
 3 files changed, 42 insertions(+), 2 deletions(-)
 create mode 100644 tests/bugs/modalg_7/bug30154_1
 create mode 100644 tests/bugs/modalg_7/bug30154_2

diff --git a/src/BRepLib/BRepLib_1.cxx b/src/BRepLib/BRepLib_1.cxx
index a5cca92896..30bcd8aedc 100644
--- a/src/BRepLib/BRepLib_1.cxx
+++ b/src/BRepLib/BRepLib_1.cxx
@@ -158,8 +158,10 @@ Standard_Boolean BRepLib::FindValidRange
 {
   if (theParV2 - theParV1 < Precision::PConfusion())
     return Standard_False;
-  
-  Standard_Real anEps = Max(theCurve.Resolution(theTolE) * 0.1, Precision::PConfusion());
+
+  Standard_Real anEps = Max(Max(theCurve.Resolution(theTolE) * 0.1,
+                                Epsilon(Max(Abs(theParV1), Abs(theParV2)))),
+                            Precision::PConfusion());
 
   if (Precision::IsInfinite(theParV1))
     theFirst = theParV1;
diff --git a/tests/bugs/modalg_7/bug30154_1 b/tests/bugs/modalg_7/bug30154_1
new file mode 100644
index 0000000000..76f046c802
--- /dev/null
+++ b/tests/bugs/modalg_7/bug30154_1
@@ -0,0 +1,15 @@
+puts "========"
+puts "0030154: Modeling Algorithms - Boolean Operation on planar geometry hangs inside BRepLib::FindValidRange()"
+puts "========"
+puts ""
+
+plane p 165424660 597500 42834196 -1 0 0
+mkface f p
+box b -94190864 -46229000 -17178478.4 519231048 93653000 120025348.8
+invert b
+
+bcut result f b
+
+checkshape result
+checkprops result -s 1.12407e+16
+checknbshapes result -wire 1 -face 1
diff --git a/tests/bugs/modalg_7/bug30154_2 b/tests/bugs/modalg_7/bug30154_2
new file mode 100644
index 0000000000..e2a7819ded
--- /dev/null
+++ b/tests/bugs/modalg_7/bug30154_2
@@ -0,0 +1,23 @@
+puts "========"
+puts "0030154: Modeling Algorithms - Boolean Operation on planar geometry hangs inside BRepLib::FindValidRange()"
+puts "========"
+puts ""
+
+set toler 3.e-7
+
+box b -94190864 -46229000 -17178478.4 519231048 93653000 120025348.8
+
+foreach e [explode b e] {
+  mkcurve c $e
+  regexp {Parameters : ([-0-9.+eE]*) ([-0-9.+eE]*)} [dump c] full t1 t2
+  set range [validrange $e]
+  set ts1 [lindex $range 0]
+  set ts2 [lindex $range 1]
+
+  set delta1 [expr $ts1 - $t1]
+  set delta2 [expr $t2 - $ts2]
+
+  if {$delta1 < 1.e-7 || $delta1 > $toler || $delta2 < 1.e-7 || $delta2 > $toler} {
+    puts "Error: incorrect computation of the valid range"
+  }
+}
\ No newline at end of file