diff --git a/CHANGELOG.md b/CHANGELOG.md
index 027ace869..ad522690a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -40,6 +40,7 @@ This section is for changes merged to the `major` branch that are not also merge
 - The pager will now show the full command instead of just its last line if the number of completions is large (#4702).
 - Tildes in file names are now properly escaped in completions (#2274)
 - A pipe at the end of a line now allows the job to continue on the next line (#1285)
+- The names `argparse`, `read`, `set`, `status`, `test` and `[` are now reserved and not allowed as function names. This prevents users unintentionally breaking stuff (#3000).
 
 ## Other significant changes
 - Command substitution output is now limited to 10 MB by default (#3822).
diff --git a/src/parser_keywords.cpp b/src/parser_keywords.cpp
index 015aac12b..12676c266 100644
--- a/src/parser_keywords.cpp
+++ b/src/parser_keywords.cpp
@@ -22,7 +22,7 @@ static const wcstring_list_t block_keywords({L"for", L"while", L"if", L"function
 bool parser_keywords_is_block(const wcstring &word) { return contains(block_keywords, word); }
 
 static const wcstring_list_t reserved_keywords({L"end", L"case", L"else", L"return", L"continue",
-                                                L"break"});
+                                                L"break", L"argparse", L"read", L"set", L"status", L"test", L"["});
 bool parser_keywords_is_reserved(const wcstring &word) {
     return parser_keywords_is_block(word) || parser_keywords_is_subcommand(word) ||
            contains(reserved_keywords, word);
diff --git a/tests/function.err b/tests/function.err
index 06cdb1698..2d69cbb05 100644
--- a/tests/function.err
+++ b/tests/function.err
@@ -22,3 +22,10 @@ function name5 abc --argument-names def ; end
 
 ####################
 # Checking that the copied functions are identical other than the name
+
+####################
+# Checking reserved names
+fish: function: The name 'test' is reserved,
+and can not be used as a function name
+function test; echo banana; end
+^
diff --git a/tests/function.in b/tests/function.in
index c0b324f97..5f64ed777 100644
--- a/tests/function.in
+++ b/tests/function.in
@@ -46,4 +46,6 @@ logmsg Checking that the copied functions are identical other than the name
 diff (functions name1 | psub) (functions name1a | psub)
 diff (functions name3 | psub) (functions name3a | psub)
 
+logmsg Checking reserved names
+function test; echo banana; end
 exit 0
diff --git a/tests/function.out b/tests/function.out
index 064f58164..95a79ed2f 100644
--- a/tests/function.out
+++ b/tests/function.out
@@ -70,3 +70,6 @@ Function name4 not found as expected
 < function name3 --argument arg1 arg2
 ---
 > function name3a --argument arg1 arg2
+
+####################
+# Checking reserved names