From 43744bcae902b7211a81467d442188cd18958200 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9a=20Saviot?= <lea.saviot@numworks.com>
Date: Wed, 15 Jul 2020 10:59:20 +0200
Subject: [PATCH] [poincare/power] Fix shallowReduce

Scenario: f(x) = 0->0
In graph, go to x = e^(f(0))
---
 poincare/src/power.cpp           |  2 +-
 poincare/test/helper.cpp         |  7 ++++++-
 poincare/test/helper.h           |  2 ++
 poincare/test/simplification.cpp | 16 ++++++++++++++++
 4 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/poincare/src/power.cpp b/poincare/src/power.cpp
index d5913e835..299221d86 100644
--- a/poincare/src/power.cpp
+++ b/poincare/src/power.cpp
@@ -406,7 +406,7 @@ Expression Power::shallowReduce(ExpressionNode::ReductionContext reductionContex
   // Step 1: Handle the units
   {
     Expression indexUnit;
-    index.removeUnit(&indexUnit);
+    index = index.removeUnit(&indexUnit);
     if (!indexUnit.isUninitialized()) {
       // There must be no unit in the exponent
       return replaceWithUndefinedInPlace();
diff --git a/poincare/test/helper.cpp b/poincare/test/helper.cpp
index 5d14942c1..417fba00c 100644
--- a/poincare/test/helper.cpp
+++ b/poincare/test/helper.cpp
@@ -79,8 +79,13 @@ Poincare::Expression parse_expression(const char * expression, Context * context
 void assert_simplify(const char * expression, Preferences::AngleUnit angleUnit, Preferences::ComplexFormat complexFormat, ExpressionNode::ReductionTarget target) {
   Shared::GlobalContext globalContext;
   Expression e = parse_expression(expression, &globalContext, false);
+  assert_expression_simplify(e, angleUnit, complexFormat, target, expression);
+}
+
+void assert_expression_simplify(Expression e, Preferences::AngleUnit angleUnit, Preferences::ComplexFormat complexFormat, ExpressionNode::ReductionTarget target, const char * printIfFailure) {
+  Shared::GlobalContext globalContext;
   e = e.reduce(ExpressionNode::ReductionContext(&globalContext, complexFormat, angleUnit, target));
-  quiz_assert_print_if_failure(!(e.isUninitialized()), expression);
+  quiz_assert_print_if_failure(!(e.isUninitialized()), printIfFailure);
 }
 
 void assert_parsed_expression_simplify_to(const char * expression, const char * simplifiedExpression, ExpressionNode::ReductionTarget target, Preferences::AngleUnit angleUnit, Preferences::ComplexFormat complexFormat, ExpressionNode::SymbolicComputation symbolicComputation, ExpressionNode::UnitConversion unitConversion) {
diff --git a/poincare/test/helper.h b/poincare/test/helper.h
index 6ef23c361..335efb1a3 100644
--- a/poincare/test/helper.h
+++ b/poincare/test/helper.h
@@ -41,6 +41,8 @@ Poincare::Expression parse_expression(const char * expression, Poincare::Context
 
 void assert_simplify(const char * expression, Poincare::Preferences::AngleUnit angleUnit = Radian, Poincare::Preferences::ComplexFormat complexFormat = Cartesian, Poincare::ExpressionNode::ReductionTarget target = User);
 
+void assert_expression_simplify(Poincare::Expression expression, Poincare::Preferences::AngleUnit angleUnit = Radian, Poincare::Preferences::ComplexFormat complexFormat = Cartesian, Poincare::ExpressionNode::ReductionTarget target = User, const char * printIfFailure = "Error");
+
 void assert_parsed_expression_simplify_to(const char * expression, const char * simplifiedExpression, Poincare::ExpressionNode::ReductionTarget target = User, Poincare::Preferences::AngleUnit angleUnit = Radian, Poincare::Preferences::ComplexFormat complexFormat = Cartesian, Poincare::ExpressionNode::SymbolicComputation symbolicComputation = ReplaceAllDefinedSymbolsWithDefinition, Poincare::ExpressionNode::UnitConversion unitConversion = DefaultUnitConversion);
 
 // Approximation
diff --git a/poincare/test/simplification.cpp b/poincare/test/simplification.cpp
index 32094d201..00a246928 100644
--- a/poincare/test/simplification.cpp
+++ b/poincare/test/simplification.cpp
@@ -1304,6 +1304,22 @@ QUIZ_CASE(poincare_simplification_user_function) {
   Ion::Storage::sharedStorage()->recordNamed("f.func").destroy();
 }
 
+QUIZ_CASE(poincare_simplification_user_function_with_convert) {
+  /* User defined function
+   * f: x → 0→0
+   * It cannot be created with a const char *, so we create it by hand. */
+  Expression e = Store::Builder(
+      UnitConvert::Builder(
+        Rational::Builder(0),
+        Rational::Builder(0)),
+      Function::Builder(
+        "f", 1,
+        Symbol::Builder('x')));
+  assert_expression_simplify(e);
+  assert_simplify("e^(f(0))", Radian, Polar);
+  Ion::Storage::sharedStorage()->recordNamed("f.func").destroy();
+}
+
 QUIZ_CASE(poincare_simplification_mix) {
   // Root at denominator
   assert_parsed_expression_simplify_to("1/(√(2)+√(3))", "√(3)-√(2)");