Only show the first parse error

src/parser_api.jl

@@ -17,7 +17,13 @@ end
 
 function Base.showerror(io::IO, err::ParseError)
     println(io, "ParseError:")
-    show_diagnostics(io, err.diagnostics, err.source)
+    # Only show the first parse error for now - later errors are often
+    # misleading due to the way recovery works
+    i = findfirst(is_error, err.diagnostics)
+    if isnothing(i)
+        i = lastindex(err.diagnostics)
+    end
+    show_diagnostics(io, err.diagnostics[1:i], err.source)
 end
 
 """

test/parser_api.jl

@@ -117,28 +117,56 @@ end
 
 @testset "ParseError printing" begin
     try
-        JuliaSyntax.parsestmt(JuliaSyntax.SyntaxNode, "a -- b -- c", filename="somefile.jl")
+        parsestmt(SyntaxNode, "a -- b -- c", filename="somefile.jl")
         @assert false "error should be thrown"
     catch exc
         @test exc isa JuliaSyntax.ParseError
         @test sprint(showerror, exc) == """
             ParseError:
             # Error @ somefile.jl:1:3
             a -- b -- c
-            # └┘ ── invalid operator
-            # Error @ somefile.jl:1:8
-            a -- b -- c
-            #      └┘ ── invalid operator"""
+            # └┘ ── invalid operator"""
         @test occursin("Stacktrace:\n", sprint(showerror, exc, catch_backtrace()))
         file_url = JuliaSyntax._file_url("somefile.jl")
         @test sprint(showerror, exc, context=:color=>true) == """
             ParseError:
             \e[90m# Error @ \e[0;0m\e]8;;$file_url#1:3\e\\\e[90msomefile.jl:1:3\e[0;0m\e]8;;\e\\
             a \e[48;2;120;70;70m--\e[0;0m b -- c
-            \e[90m# └┘ ── \e[0;0m\e[91minvalid operator\e[0;0m
-            \e[90m# Error @ \e[0;0m\e]8;;$file_url#1:8\e\\\e[90msomefile.jl:1:8\e[0;0m\e]8;;\e\\
-            a -- b \e[48;2;120;70;70m--\e[0;0m c
-            \e[90m#      └┘ ── \e[0;0m\e[91minvalid operator\e[0;0m"""
+            \e[90m# └┘ ── \e[0;0m\e[91minvalid operator\e[0;0m"""
+    end
+
+    try
+        # Test that warnings are printed first followed by only the first error
+        parsestmt(SyntaxNode, """
+           @(a)
+           x -- y
+           z -- y""", filename="somefile.jl")
+        @assert false "error should be thrown"
+    catch exc
+        @test exc isa JuliaSyntax.ParseError
+        @test sprint(showerror, exc) == """
+            ParseError:
+            # Warning @ somefile.jl:1:2
+            @(a)
+            #└─┘ ── parenthesizing macro names is unnecessary
+            # Error @ somefile.jl:2:1
+            @(a)
+            x
+            ╙ ── unexpected text after parsing statement"""
+    end
+
+    try
+        # Test that initial warnings are always printed
+        parsestmt(SyntaxNode, """
+           @(a)""", filename="somefile.jl")
+        @assert false "error should be thrown"
+    catch exc
+        @test exc isa JuliaSyntax.ParseError
+        @test sprint(showerror, exc) == """
+            ParseError:
+            # Warning @ somefile.jl:1:2
+            @(a)
+            #└─┘ ── parenthesizing macro names is unnecessary"""
     end
 end