From ab600f8ce704cafd519581ad62858d00f82a40d8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gunnar=20Farneb=C3=A4ck?=
 <gunnar.farneback@contextvision.se>
Date: Mon, 16 Aug 2021 19:32:52 +0200
Subject: [PATCH] [REPL] 0nly do NFD normalization for latex tab-completion
 help if no match without it (#41870)

---
 stdlib/REPL/src/docview.jl | 8 ++++++--
 test/docs.jl               | 2 ++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/stdlib/REPL/src/docview.jl b/stdlib/REPL/src/docview.jl
index 2e5fc361d8cbc..f4467b3e787bc 100644
--- a/stdlib/REPL/src/docview.jl
+++ b/stdlib/REPL/src/docview.jl
@@ -403,9 +403,13 @@ function symbol_latex(s::String)
     return get(symbols_latex, s, "")
 end
 function repl_latex(io::IO, s::String)
-    # decompose NFC-normalized identifier to match tab-completion input
-    s = normalize(s, :NFD)
     latex = symbol_latex(s)
+    if isempty(latex)
+        # Decompose NFC-normalized identifier to match tab-completion
+        # input if the first search came up empty.
+        s = normalize(s, :NFD)
+        latex = symbol_latex(s)
+    end
     if !isempty(latex)
         print(io, "\"")
         printstyled(io, s, color=:cyan)
diff --git a/test/docs.jl b/test/docs.jl
index 05442df9d4cbe..41c3746d7476f 100644
--- a/test/docs.jl
+++ b/test/docs.jl
@@ -1271,6 +1271,8 @@ end
 
 # issue #36378 (\u1e8b and x\u307 are the fully composed and decomposed forms of ẋ, respectively)
 @test sprint(repl_latex, "\u1e8b") == "\"x\u307\" can be typed by x\\dot<tab>\n\n"
+# issue 39814
+@test sprint(repl_latex, "\u2209") == "\"\u2209\" can be typed by \\notin<tab>\n\n"
 
 # issue #15684
 begin