Add basic tests

Author: tecosaur

test/runtests.jl

@@ -0,0 +1,26 @@
+# This file is a part of Julia. License is MIT: https://julialang.org/license
+
+using JuliaSyntaxHighlighting: highlight, highlight!
+using Test
+
+# We could go to the effort of testing each individual highlight face,
+# however here we're aiming for the much lower bar of ensuring that
+# `highlight` consistently returns a reasonable result.
+# This also avoids testing as much of the particulars of JuliaSyntax.
+
+sum1to8_highlighted = Base.AnnotatedString("sum(1:8)", [
+    (1:3, :face => :julia_funcall),
+    (4:4, :face => :julia_rainbow_paren_1),
+    (5:5, :face => :julia_number),
+    (6:6, :face => :julia_operator),
+    (7:7, :face => :julia_number),
+    (8:8, :face => :julia_rainbow_paren_1)
+])
+
+@test highlight("sum(1:8)") ==sum1to8_highlighted
+@test highlight(IOBuffer("sum(1:8)")) ==sum1to8_highlighted
+@test highlight(IOContext(IOBuffer("sum(1:8)"))) ==sum1to8_highlighted
+
+astr_sum1to8 = Base.AnnotatedString("sum(1:8)")
+@test highlight!(astr_sum1to8) == sum1to8_highlighted
+@test astr_sum1to8 == sum1to8_highlighted