rsmgp_sys/path/
mod.rs

1// Copyright (c) 2016-2021 Memgraph Ltd. [https://memgraph.com]
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14//! All related to a graph path.
15
16use crate::edge::*;
17use crate::memgraph::*;
18use crate::mgp::*;
19use crate::result::*;
20use crate::vertex::*;
21// Required here, if not present tests linking fails.
22#[double]
23use crate::mgp::ffi;
24use mockall_double::double;
25
26pub struct Path {
27    ptr: *mut mgp_path,
28    memgraph: Memgraph,
29}
30impl Drop for Path {
31    fn drop(&mut self) {
32        unsafe {
33            if !self.ptr.is_null() {
34                ffi::mgp_path_destroy(self.ptr);
35            }
36        }
37    }
38}
39
40impl Path {
41    pub(crate) fn new(ptr: *mut mgp_path, memgraph: &Memgraph) -> Path {
42        #[cfg(not(test))]
43        assert!(
44            !ptr.is_null(),
45            "Unable to create path because the given pointer is null."
46        );
47
48        Path {
49            ptr,
50            memgraph: memgraph.clone(),
51        }
52    }
53
54    /// Creates a new Path based on [mgp_path].
55    pub(crate) unsafe fn mgp_copy(
56        mgp_path: *const mgp_path,
57        memgraph: &Memgraph,
58    ) -> MgpResult<Path> {
59        #[cfg(not(test))]
60        assert!(
61            !mgp_path.is_null(),
62            "Unable to make path copy because the given pointer is null."
63        );
64
65        let mgp_copy = ffi::mgp_path_copy(mgp_path, memgraph.memory_ptr());
66        if mgp_copy.is_null() {
67            return Err(MgpError::UnableToCopyPath);
68        }
69        Ok(Path::new(mgp_copy, &memgraph))
70    }
71
72    /// Returns the underlying [mgp_path] pointer.
73    pub(crate) fn mgp_ptr(&self) -> *const mgp_path {
74        self.ptr
75    }
76
77    pub fn size(&self) -> u64 {
78        unsafe { ffi::mgp_path_size(self.ptr) }
79    }
80
81    /// Makes a new [Path] based on the starting [Vertex] object.
82    pub fn make_with_start(vertex: &Vertex, memgraph: &Memgraph) -> MgpResult<Path> {
83        unsafe {
84            let mgp_path = ffi::mgp_path_make_with_start(vertex.mgp_ptr(), memgraph.memory_ptr());
85            if mgp_path.is_null() {
86                return Err(MgpError::UnableToCreatePathWithStartVertex);
87            }
88            Ok(Path::new(mgp_path, &memgraph))
89        }
90    }
91
92    /// Fails if the current last vertex in the path is not part of the given edge or if there is
93    /// no memory to expand the path.
94    pub fn expand(&self, edge: &Edge) -> MgpResult<()> {
95        unsafe {
96            let mgp_result = ffi::mgp_path_expand(self.ptr, edge.mgp_ptr());
97            if mgp_result == 0 {
98                return Err(MgpError::UnableToExpandPath);
99            }
100            Ok(())
101        }
102    }
103
104    pub fn vertex_at(&self, index: u64) -> MgpResult<Vertex> {
105        unsafe {
106            let mgp_vertex = ffi::mgp_path_vertex_at(self.ptr, index);
107            if mgp_vertex.is_null() {
108                return Err(MgpError::OutOfBoundPathVertexIndex);
109            }
110            Vertex::mgp_copy(mgp_vertex, &self.memgraph)
111        }
112    }
113
114    pub fn edge_at(&self, index: u64) -> MgpResult<Edge> {
115        unsafe {
116            let mgp_edge = ffi::mgp_path_edge_at(self.ptr, index);
117            if mgp_edge.is_null() {
118                return Err(MgpError::OutOfBoundPathEdgeIndex);
119            }
120            Edge::mgp_copy(mgp_edge, &self.memgraph)
121        }
122    }
123}
124
125#[cfg(test)]
126mod tests;
rsmgp_sys/path/mod.rs

rsmgp_sys/path/
mod.rs
