graphql_tools/validation/rules/
no_unused_fragments.rs

1use super::ValidationRule;
2use crate::ast::{visit_document, OperationVisitor, OperationVisitorContext};
3use crate::static_graphql::query::*;
4use crate::validation::utils::{ValidationError, ValidationErrorContext};
5
6/// No unused fragments
7///
8/// A GraphQL document is only valid if all fragment definitions are spread
9/// within operations, or spread within other fragments spread within operations.
10///
11/// See https://spec.graphql.org/draft/#sec-Fragments-Must-Be-Used
12pub struct NoUnusedFragments<'a> {
13    fragments_in_use: Vec<&'a str>,
14}
15
16impl<'a> OperationVisitor<'a, ValidationErrorContext> for NoUnusedFragments<'a> {
17    fn enter_fragment_spread(
18        &mut self,
19        _: &mut OperationVisitorContext,
20        _: &mut ValidationErrorContext,
21        fragment_spread: &'a FragmentSpread,
22    ) {
23        self.fragments_in_use
24            .push(fragment_spread.fragment_name.as_str());
25    }
26
27    fn leave_document(
28        &mut self,
29        visitor_context: &mut OperationVisitorContext,
30        user_context: &mut ValidationErrorContext,
31        _document: &Document,
32    ) {
33        visitor_context
34            .known_fragments
35            .iter()
36            .filter_map(|(fragment_name, _fragment)| {
37                if !self.fragments_in_use.contains(fragment_name) {
38                    Some(fragment_name)
39                } else {
40                    None
41                }
42            })
43            .for_each(|unused_fragment_name| {
44                user_context.report_error(ValidationError {
45                    error_code: self.error_code(),
46                    locations: vec![],
47                    message: format!("Fragment \"{}\" is never used.", unused_fragment_name),
48                });
49            });
50    }
51}
52
53impl<'a> Default for NoUnusedFragments<'a> {
54    fn default() -> Self {
55        Self::new()
56    }
57}
58
59impl<'a> NoUnusedFragments<'a> {
60    pub fn new() -> Self {
61        NoUnusedFragments {
62            fragments_in_use: Vec::new(),
63        }
64    }
65}
66
67impl<'n> ValidationRule for NoUnusedFragments<'n> {
68    fn error_code<'a>(&self) -> &'a str {
69        "NoUnusedFragments"
70    }
71
72    fn validate(
73        &self,
74        ctx: &mut OperationVisitorContext,
75        error_collector: &mut ValidationErrorContext,
76    ) {
77        visit_document(
78            &mut NoUnusedFragments::new(),
79            ctx.operation,
80            ctx,
81            error_collector,
82        );
83    }
84}
85
86#[test]
87fn all_fragment_names_are_used() {
88    use crate::validation::test_utils::*;
89
90    let mut plan = create_plan_from_rule(Box::new(NoUnusedFragments::new()));
91    let errors = test_operation_with_schema(
92        "{
93          human(id: 4) {
94            ...HumanFields1
95            ... on Human {
96              ...HumanFields2
97            }
98          }
99        }
100        fragment HumanFields1 on Human {
101          name
102          ...HumanFields3
103        }
104        fragment HumanFields2 on Human {
105          name
106        }
107        fragment HumanFields3 on Human {
108          name
109        }",
110        TEST_SCHEMA,
111        &mut plan,
112    );
113
114    assert_eq!(get_messages(&errors).len(), 0);
115}
116
117#[test]
118fn all_fragment_names_are_used_by_multiple_operations() {
119    use crate::validation::test_utils::*;
120
121    let mut plan = create_plan_from_rule(Box::new(NoUnusedFragments::new()));
122    let errors = test_operation_with_schema(
123        "query Foo {
124          human(id: 4) {
125            ...HumanFields1
126          }
127        }
128        query Bar {
129          human(id: 4) {
130            ...HumanFields2
131          }
132        }
133        fragment HumanFields1 on Human {
134          name
135          ...HumanFields3
136        }
137        fragment HumanFields2 on Human {
138          name
139        }
140        fragment HumanFields3 on Human {
141          name
142        }
143  ",
144        TEST_SCHEMA,
145        &mut plan,
146    );
147
148    assert_eq!(get_messages(&errors).len(), 0);
149}
150
151#[test]
152fn contains_unknown_fragments() {
153    use crate::validation::test_utils::*;
154
155    let mut plan = create_plan_from_rule(Box::new(NoUnusedFragments::new()));
156    let errors = test_operation_with_schema(
157        "query Foo {
158          human(id: 4) {
159            ...HumanFields1
160          }
161        }
162        query Bar {
163          human(id: 4) {
164            ...HumanFields2
165          }
166        }
167        fragment HumanFields1 on Human {
168          name
169          ...HumanFields3
170        }
171        fragment HumanFields2 on Human {
172          name
173        }
174        fragment HumanFields3 on Human {
175          name
176        }
177        fragment Unused1 on Human {
178          name
179        }
180        fragment Unused2 on Human {
181          name
182        }
183  ",
184        TEST_SCHEMA,
185        &mut plan,
186    );
187
188    let messages = get_messages(&errors);
189    assert_eq!(messages.len(), 2);
190}
191
192// TODO: Fix this one :( It's not working
193#[test]
194#[ignore = "Fix this one :( It's not working"]
195fn contains_unknown_fragments_with_ref_cycle() {
196    use crate::validation::test_utils::*;
197
198    let mut plan = create_plan_from_rule(Box::new(NoUnusedFragments::new()));
199    let errors = test_operation_with_schema(
200        "query Foo {
201          human(id: 4) {
202            ...HumanFields1
203          }
204        }
205        query Bar {
206          human(id: 4) {
207            ...HumanFields2
208          }
209        }
210        fragment HumanFields1 on Human {
211          name
212          ...HumanFields3
213        }
214        fragment HumanFields2 on Human {
215          name
216        }
217        fragment HumanFields3 on Human {
218          name
219        }
220        fragment Unused1 on Human {
221          name
222          ...Unused2
223        }
224        fragment Unused2 on Human {
225          name
226          ...Unused1
227        }
228  ",
229        TEST_SCHEMA,
230        &mut plan,
231    );
232
233    let messages = get_messages(&errors);
234    assert_eq!(messages.len(), 2);
235    assert_eq!(
236        messages,
237        vec![
238            "Fragment \"Unused1\" is never used.",
239            "Fragment \"Unused2\" is never used."
240        ]
241    );
242}
243
244#[test]
245fn contains_unknown_and_undef_fragments() {
246    use crate::validation::test_utils::*;
247
248    let mut plan = create_plan_from_rule(Box::new(NoUnusedFragments::new()));
249    let errors = test_operation_with_schema(
250        "query Foo {
251          human(id: 4) {
252            ...bar
253          }
254        }
255        fragment foo on Human {
256          name
257        }
258  ",
259        TEST_SCHEMA,
260        &mut plan,
261    );
262
263    let messages = get_messages(&errors);
264    assert_eq!(messages.len(), 1);
265    assert_eq!(messages, vec!["Fragment \"foo\" is never used.",]);
266}
graphql_tools/validation/rules/no_unused_fragments.rs

graphql_tools/validation/rules/
no_unused_fragments.rs
