checker: fix missing map float key duplicated checking (fix #25098) (#25117)

Author: felipensp

vlib/v/checker/checker.v

@@ -5293,6 +5293,15 @@ fn (mut c Checker) check_dup_keys(node &ast.MapInit, i int) {
 				}
 			}
 		}
+	} else if key_i is ast.FloatLiteral {
+		for j in 0 .. i {
+			key_j := node.keys[j]
+			if key_j is ast.FloatLiteral {
+				if key_i.val.f64() == key_j.val.f64() {
+					c.error('duplicate key "${key_i.val}" in map literal', key_i.pos)
+				}
+			}
+		}
 	}
 }
 

vlib/v/checker/tests/map_repeated_float_key_err.out

@@ -0,0 +1,14 @@
+vlib/v/checker/tests/map_repeated_float_key_err.vv:5:3: error: duplicate key "1.e-06" in map literal
+    3 |         0.000001: 'small-1'
+    4 |         0.00001:  'small-2'
+    5 |         1.e-06:   'small-3'
+      |         ~~~~~~
+    6 |         0.00001:  'small-4'
+    7 |     }
+vlib/v/checker/tests/map_repeated_float_key_err.vv:6:3: error: duplicate key "0.00001" in map literal
+    4 |         0.00001:  'small-2'
+    5 |         1.e-06:   'small-3'
+    6 |         0.00001:  'small-4'
+      |         ~~~~~~~
+    7 |     }
+    8 |     dump(m64)

vlib/v/checker/tests/map_repeated_float_key_err.vv

@@ -0,0 +1,9 @@
+fn main() {
+	m64 := {
+		0.000001: 'small-1'
+		0.00001:  'small-2'
+		1.e-06:   'small-3'
+		0.00001:  'small-4'
+	}
+	dump(m64)
+}