From 73331de0c360f726766b7687bb57c36cf5f8b3e4 Mon Sep 17 00:00:00 2001
From: jverzani <jverzani@gmail.com>
Date: Wed, 22 Dec 2021 15:15:15 -0500
Subject: [PATCH 1/2] conversion from ChebyshevT; close issue #372

---
 Project.toml                  |  2 +-
 src/polynomials/ChebyshevT.jl |  3 ++-
 test/ChebyshevT.jl            | 10 ++++++++--
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/Project.toml b/Project.toml
index 555ba30a..9bfadb73 100644
--- a/Project.toml
+++ b/Project.toml
@@ -2,7 +2,7 @@ name = "Polynomials"
 uuid = "f27b6e38-b328-58d1-80ce-0feddd5e7a45"
 license = "MIT"
 author = "JuliaMath"
-version = "2.0.19"
+version = "2.0.20"
 
 [deps]
 Intervals = "d8418881-c3e1-53bb-8760-2df7ec849ed5"
diff --git a/src/polynomials/ChebyshevT.jl b/src/polynomials/ChebyshevT.jl
index d5c6d7d7..d215a820 100644
--- a/src/polynomials/ChebyshevT.jl
+++ b/src/polynomials/ChebyshevT.jl
@@ -57,7 +57,8 @@ end
 @register ChebyshevT
 
 function Base.convert(P::Type{<:Polynomial}, ch::ChebyshevT)
-    T = eltype(P)
+
+    T = _eltype(P,ch)
     X = indeterminate(P,ch)
     Q = ⟒(P){T,X}
 
diff --git a/test/ChebyshevT.jl b/test/ChebyshevT.jl
index 6dad84bd..00fa3228 100644
--- a/test/ChebyshevT.jl
+++ b/test/ChebyshevT.jl
@@ -166,7 +166,7 @@ end
     # issue 326 evaluate outside of domain
     @test Polynomials.evalpoly(2, c1, false) ≈ fn(2)
     @test Polynomials.evalpoly(3, c1, false) ≈ fn(3)
-    
+
     # GCD
     c1 = ChebyshevT([1, 2, 3])
     c2 = ChebyshevT([3, 2, 1])
@@ -221,6 +221,12 @@ end
     # issue #295
     x = BigFloat[-2/3, -1/3, 1/3, 2/4]
     y = BigFloat[1, 2, 3, 4]
-    fit(ChebyshevT, x, y, 1) 
+    fit(ChebyshevT, x, y, 1)
+
+    # issue #372
+    xs = [0,0,1]
+    @test eltype(convert(Polynomial, ChebyshevT{Float64}(xs))) == Float64
+    @test eltype(convert(Polynomial, ChebyshevT{BigFloat}(xs))) == BigFloat
+    @test eltype(convert(Polynomial{BigFloat}, ChebyshevT(xs))) == BigFloat
 
 end

From 157f13f5d2dac9104ed53bbb8eea70bdfedfefe0 Mon Sep 17 00:00:00 2001
From: jverzani <jverzani@gmail.com>
Date: Wed, 22 Dec 2021 21:02:59 -0500
Subject: [PATCH 2/2] doctest fix

---
 docs/src/polynomials/chebyshev.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/src/polynomials/chebyshev.md b/docs/src/polynomials/chebyshev.md
index e711a9fb..38d79854 100644
--- a/docs/src/polynomials/chebyshev.md
+++ b/docs/src/polynomials/chebyshev.md
@@ -31,7 +31,7 @@ ChebyshevT(1⋅T_0(x) + 3⋅T_2(x) + 4⋅T_3(x))
 
 
 julia> p = convert(Polynomial, c)
-Polynomial(-2.0 - 12.0*x + 6.0*x^2 + 16.0*x^3)
+Polynomial(-2 - 12*x + 6*x^2 + 16*x^3)
 
 julia> convert(ChebyshevT, p)
 ChebyshevT(1.0⋅T_0(x) + 3.0⋅T_2(x) + 4.0⋅T_3(x))