4 files changed, 45 insertions, 3 deletions
diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 612c3be368..8cf505587d 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -15698,11 +15698,15 @@ static void f_split(typval_T *argvars, typval_T *rettv, FunPtr fptr)
 static void f_str2float(typval_T *argvars, typval_T *rettv, FunPtr fptr)
 {
   char_u *p = skipwhite((const char_u *)tv_get_string(&argvars[0]));
+  bool isneg = (*p == '-');
 
-  if (*p == '+') {
+  if (*p == '+' || *p == '-') {
     p = skipwhite(p + 1);
   }
   (void)string2float((char *)p, &rettv->vval.v_float);
+  if (isneg) {
+    rettv->vval.v_float *= -1;
+  }
   rettv->v_type = VAR_FLOAT;
 }
 
@@ -15722,7 +15726,8 @@ static void f_str2nr(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   }
 
   char_u *p = skipwhite((const char_u *)tv_get_string(&argvars[0]));
-  if (*p == '+') {
+  bool isneg = (*p == '-');
+  if (*p == '+' || *p == '-') {
     p = skipwhite(p + 1);
   }
   switch (base) {
@@ -15743,7 +15748,11 @@ static void f_str2nr(typval_T *argvars, typval_T *rettv, FunPtr fptr)
     }
   }
   vim_str2nr(p, NULL, NULL, what, &n, NULL, 0);
-  rettv->vval.v_number = n;
+  if (isneg) {
+    rettv->vval.v_number = -n;
+  } else {
+    rettv->vval.v_number = n;
+  }
 }
 
 /*
diff --git a/src/nvim/testdir/test_alot.vim b/src/nvim/testdir/test_alot.vim
index a250ba7493..1103778107 100644
--- a/src/nvim/testdir/test_alot.vim
+++ b/src/nvim/testdir/test_alot.vim
@@ -11,6 +11,7 @@ source test_feedkeys.vim
 source test_filter_cmd.vim
 source test_filter_map.vim
 source test_float_func.vim
+source test_functions.vim
 source test_goto.vim
 source test_jumps.vim
 source test_lambda.vim
diff --git a/src/nvim/testdir/test_float_func.vim b/src/nvim/testdir/test_float_func.vim
index 8600ce5b60..21a156e3d8 100644
--- a/src/nvim/testdir/test_float_func.vim
+++ b/src/nvim/testdir/test_float_func.vim
@@ -165,9 +165,22 @@ endfunc
 
 func Test_str2float()
   call assert_equal('1.0', string(str2float('1')))
+  call assert_equal('1.0', string(str2float(' 1 ')))
+  call assert_equal('1.0', string(str2float(' 1.0 ')))
   call assert_equal('1.23', string(str2float('1.23')))
   call assert_equal('1.23', string(str2float('1.23abc')))
   call assert_equal('1.0e40', string(str2float('1e40')))
+
+  call assert_equal('1.0', string(str2float('+1')))
+  call assert_equal('1.0', string(str2float('+1')))
+  call assert_equal('1.0', string(str2float(' +1 ')))
+  call assert_equal('1.0', string(str2float(' + 1 ')))
+
+  call assert_equal('-1.0', string(str2float('-1')))
+  call assert_equal('-1.0', string(str2float('-1')))
+  call assert_equal('-1.0', string(str2float(' -1 ')))
+  call assert_equal('-1.0', string(str2float(' - 1 ')))
+
   call assert_equal("str2float('inf')", string(str2float('1e1000')))
   call assert_equal("str2float('inf')", string(str2float('inf')))
   call assert_equal("-str2float('inf')", string(str2float('-inf')))
diff --git a/src/nvim/testdir/test_functions.vim b/src/nvim/testdir/test_functions.vim
index 3c258299c1..237a2dc820 100644
--- a/src/nvim/testdir/test_functions.vim
+++ b/src/nvim/testdir/test_functions.vim
@@ -1,3 +1,22 @@
+" Tests for various functions.
+
+func Test_str2nr()
+  call assert_equal(0, str2nr(''))
+  call assert_equal(1, str2nr('1'))
+  call assert_equal(1, str2nr(' 1 '))
+
+  call assert_equal(1, str2nr('+1'))
+  call assert_equal(1, str2nr('+ 1'))
+  call assert_equal(1, str2nr(' + 1 '))
+
+  call assert_equal(-1, str2nr('-1'))
+  call assert_equal(-1, str2nr('- 1'))
+  call assert_equal(-1, str2nr(' - 1 '))
+
+  call assert_equal(123456789, str2nr('123456789'))
+  call assert_equal(-123456789, str2nr('-123456789'))
+endfunc
+
 func Test_setbufvar_options()
   " This tests that aucmd_prepbuf() and aucmd_restbuf() properly restore the
   " window layout.