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// Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! Generate files suitable for use with [Graphviz](http://www.graphviz.org/)
//!
//! The `render` function generates output (e.g. an `output.dot` file) for
//! use with [Graphviz](http://www.graphviz.org/) by walking a labelled
//! graph. (Graphviz can then automatically lay out the nodes and edges
//! of the graph, and also optionally render the graph as an image or
//! other [output formats](
//! http://www.graphviz.org/content/output-formats), such as SVG.)
//!
//! Rather than impose some particular graph data structure on clients,
//! this library exposes two traits that clients can implement on their
//! own structs before handing them over to the rendering function.
//!
//! Note: This library does not yet provide access to the full
//! expressiveness of the [DOT language](
//! http://www.graphviz.org/doc/info/lang.html). For example, there are
//! many [attributes](http://www.graphviz.org/content/attrs) related to
//! providing layout hints (e.g. left-to-right versus top-down, which
//! algorithm to use, etc). The current intention of this library is to
//! emit a human-readable .dot file with very regular structure suitable
//! for easy post-processing.
//!
//! # Examples
//!
//! The first example uses a very simple graph representation: a list of
//! pairs of ints, representing the edges (the node set is implicit).
//! Each node label is derived directly from the int representing the node,
//! while the edge labels are all empty strings.
//!
//! This example also illustrates how to use `Cow<[T]>` to return
//! an owned vector or a borrowed slice as appropriate: we construct the
//! node vector from scratch, but borrow the edge list (rather than
//! constructing a copy of all the edges from scratch).
//!
//! The output from this example renders five nodes, with the first four
//! forming a diamond-shaped acyclic graph and then pointing to the fifth
//! which is cyclic.
//!
//! ```rust
//! use std::borrow::Cow;
//! use std::io::Write;
//!
//! type Nd = isize;
//! type Ed = (isize,isize);
//! struct Edges(Vec<Ed>);
//!
//! pub fn render_to<W: Write>(output: &mut W) {
//! let edges = Edges(vec!((0,1), (0,2), (1,3), (2,3), (3,4), (4,4)));
//! dot::render(&edges, output).unwrap()
//! }
//!
//! impl<'a> dot::Labeller<'a, Nd, Ed> for Edges {
//! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example1").unwrap() }
//!
//! fn node_id(&'a self, n: &Nd) -> dot::Id<'a> {
//! dot::Id::new(format!("N{}", *n)).unwrap()
//! }
//! }
//!
//! impl<'a> dot::GraphWalk<'a, Nd, Ed> for Edges {
//! fn nodes(&self) -> dot::Nodes<'a,Nd> {
//! // (assumes that |N| \approxeq |E|)
//! let &Edges(ref v) = self;
//! let mut nodes = Vec::with_capacity(v.len());
//! for &(s,t) in v {
//! nodes.push(s); nodes.push(t);
//! }
//! nodes.sort();
//! nodes.dedup();
//! Cow::Owned(nodes)
//! }
//!
//! fn edges(&'a self) -> dot::Edges<'a,Ed> {
//! let &Edges(ref edges) = self;
//! Cow::Borrowed(&edges[..])
//! }
//!
//! fn source(&self, e: &Ed) -> Nd { e.0 }
//!
//! fn target(&self, e: &Ed) -> Nd { e.1 }
//! }
//!
//! # pub fn main() { render_to(&mut Vec::new()) }
//! ```
//!
//! ```no_run
//! # pub fn render_to<W:std::io::Write>(output: &mut W) { unimplemented!() }
//! pub fn main() {
//! use std::fs::File;
//! let mut f = File::create("example1.dot").unwrap();
//! render_to(&mut f)
//! }
//! ```
//!
//! Output from first example (in `example1.dot`):
//!
//! ```ignore
//! digraph example1 {
//! N0[label="N0"];
//! N1[label="N1"];
//! N2[label="N2"];
//! N3[label="N3"];
//! N4[label="N4"];
//! N0 -> N1[label=""];
//! N0 -> N2[label=""];
//! N1 -> N3[label=""];
//! N2 -> N3[label=""];
//! N3 -> N4[label=""];
//! N4 -> N4[label=""];
//! }
//! ```
//!
//! The second example illustrates using `node_label` and `edge_label` to
//! add labels to the nodes and edges in the rendered graph. The graph
//! here carries both `nodes` (the label text to use for rendering a
//! particular node), and `edges` (again a list of `(source,target)`
//! indices).
//!
//! This example also illustrates how to use a type (in this case the edge
//! type) that shares substructure with the graph: the edge type here is a
//! direct reference to the `(source,target)` pair stored in the graph's
//! internal vector (rather than passing around a copy of the pair
//! itself). Note that this implies that `fn edges(&'a self)` must
//! construct a fresh `Vec<&'a (usize,usize)>` from the `Vec<(usize,usize)>`
//! edges stored in `self`.
//!
//! Since both the set of nodes and the set of edges are always
//! constructed from scratch via iterators, we use the `collect()` method
//! from the `Iterator` trait to collect the nodes and edges into freshly
//! constructed growable `Vec` values (rather use the `into`
//! from the `IntoCow` trait as was used in the first example
//! above).
//!
//! The output from this example renders four nodes that make up the
//! Hasse-diagram for the subsets of the set `{x, y}`. Each edge is
//! labelled with the &sube; character (specified using the HTML character
//! entity `&sube`).
//!
//! ```rust
//! use std::io::Write;
//!
//! type Nd = usize;
//! type Ed<'a> = &'a (usize, usize);
//! struct Graph { nodes: Vec<&'static str>, edges: Vec<(usize,usize)> }
//!
//! pub fn render_to<W: Write>(output: &mut W) {
//! let nodes = vec!("{x,y}","{x}","{y}","{}");
//! let edges = vec!((0,1), (0,2), (1,3), (2,3));
//! let graph = Graph { nodes: nodes, edges: edges };
//!
//! dot::render(&graph, output).unwrap()
//! }
//!
//! impl<'a> dot::Labeller<'a, Nd, Ed<'a>> for Graph {
//! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example2").unwrap() }
//! fn node_id(&'a self, n: &Nd) -> dot::Id<'a> {
//! dot::Id::new(format!("N{}", n)).unwrap()
//! }
//! fn node_label<'b>(&'b self, n: &Nd) -> dot::LabelText<'b> {
//! dot::LabelText::LabelStr(self.nodes[*n].into())
//! }
//! fn edge_label<'b>(&'b self, _: &Ed) -> dot::LabelText<'b> {
//! dot::LabelText::LabelStr("&sube;".into())
//! }
//! }
//!
//! impl<'a> dot::GraphWalk<'a, Nd, Ed<'a>> for Graph {
//! fn nodes(&self) -> dot::Nodes<'a,Nd> { (0..self.nodes.len()).collect() }
//! fn edges(&'a self) -> dot::Edges<'a,Ed<'a>> { self.edges.iter().collect() }
//! fn source(&self, e: &Ed) -> Nd { e.0 }
//! fn target(&self, e: &Ed) -> Nd { e.1 }
//! }
//!
//! # pub fn main() { render_to(&mut Vec::new()) }
//! ```
//!
//! ```no_run
//! # pub fn render_to<W:std::io::Write>(output: &mut W) { unimplemented!() }
//! pub fn main() {
//! use std::fs::File;
//! let mut f = File::create("example2.dot").unwrap();
//! render_to(&mut f)
//! }
//! ```
//!
//! The third example is similar to the second, except now each node and
//! edge now carries a reference to the string label for each node as well
//! as that node's index. (This is another illustration of how to share
//! structure with the graph itself, and why one might want to do so.)
//!
//! The output from this example is the same as the second example: the
//! Hasse-diagram for the subsets of the set `{x, y}`.
//!
//! ```rust
//! use std::io::Write;
//!
//! type Nd<'a> = (usize, &'a str);
//! type Ed<'a> = (Nd<'a>, Nd<'a>);
//! struct Graph { nodes: Vec<&'static str>, edges: Vec<(usize,usize)> }
//!
//! pub fn render_to<W: Write>(output: &mut W) {
//! let nodes = vec!("{x,y}","{x}","{y}","{}");
//! let edges = vec!((0,1), (0,2), (1,3), (2,3));
//! let graph = Graph { nodes: nodes, edges: edges };
//!
//! dot::render(&graph, output).unwrap()
//! }
//!
//! impl<'a> dot::Labeller<'a, Nd<'a>, Ed<'a>> for Graph {
//! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example3").unwrap() }
//! fn node_id(&'a self, n: &Nd<'a>) -> dot::Id<'a> {
//! dot::Id::new(format!("N{}", n.0)).unwrap()
//! }
//! fn node_label<'b>(&'b self, n: &Nd<'b>) -> dot::LabelText<'b> {
//! let &(i, _) = n;
//! dot::LabelText::LabelStr(self.nodes[i].into())
//! }
//! fn edge_label<'b>(&'b self, _: &Ed<'b>) -> dot::LabelText<'b> {
//! dot::LabelText::LabelStr("&sube;".into())
//! }
//! }
//!
//! impl<'a> dot::GraphWalk<'a, Nd<'a>, Ed<'a>> for Graph {
//! fn nodes(&'a self) -> dot::Nodes<'a,Nd<'a>> {
//! self.nodes.iter().map(|s| &s[..]).enumerate().collect()
//! }
//! fn edges(&'a self) -> dot::Edges<'a,Ed<'a>> {
//! self.edges.iter()
//! .map(|&(i,j)|((i, &self.nodes[i][..]),
//! (j, &self.nodes[j][..])))
//! .collect()
//! }
//! fn source(&self, e: &Ed<'a>) -> Nd<'a> { e.0 }
//! fn target(&self, e: &Ed<'a>) -> Nd<'a> { e.1 }
//! }
//!
//! # pub fn main() { render_to(&mut Vec::new()) }
//! ```
//!
//! ```no_run
//! # pub fn render_to<W:std::io::Write>(output: &mut W) { unimplemented!() }
//! pub fn main() {
//! use std::fs::File;
//! let mut f = File::create("example3.dot").unwrap();
//! render_to(&mut f)
//! }
//! ```
//!
//! # References
//!
//! * [Graphviz](http://www.graphviz.org/)
//!
//! * [DOT language](http://www.graphviz.org/doc/info/lang.html)
#![crate_name = "dot"]
#![crate_type = "rlib"]
#![crate_type = "dylib"]
#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
html_root_url = "https://doc.rust-lang.org/nightly/")]
use self::LabelText::*;
use std::borrow::Cow;
use std::io::prelude::*;
use std::io;
/// The text for a graphviz label on a node or edge.
pub enum LabelText<'a> {
/// This kind of label preserves the text directly as is.
///
/// Occurrences of backslashes (`\`) are escaped, and thus appear
/// as backslashes in the rendered label.
LabelStr(Cow<'a, str>),
/// This kind of label uses the graphviz label escString type:
/// http://www.graphviz.org/content/attrs#kescString
///
/// Occurrences of backslashes (`\`) are not escaped; instead they
/// are interpreted as initiating an escString escape sequence.
///
/// Escape sequences of particular interest: in addition to `\n`
/// to break a line (centering the line preceding the `\n`), there
/// are also the escape sequences `\l` which left-justifies the
/// preceding line and `\r` which right-justifies it.
EscStr(Cow<'a, str>),
/// This uses a graphviz [HTML string label][html]. The string is
/// printed exactly as given, but between `<` and `>`. **No
/// escaping is performed.**
///
/// [html]: http://www.graphviz.org/content/node-shapes#html
HtmlStr(Cow<'a, str>),
}
/// The style for a node or edge.
/// See http://www.graphviz.org/doc/info/attrs.html#k:style for descriptions.
/// Note that some of these are not valid for edges.
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum Style {
None,
Invisible,
Solid,
Dashed,
Dotted,
Bold,
Rounded,
Diagonals,
Filled,
Striped,
Wedged,
}
impl Style {
pub fn as_slice(self) -> &'static str {
match self {
Style::None => "",
Style::Invisible => "invis",
Style::Solid => "solid",
Style::Dashed => "dashed",
Style::Dotted => "dotted",
Style::Bold => "bold",
Style::Rounded => "rounded",
Style::Diagonals => "diagonals",
Style::Filled => "filled",
Style::Striped => "striped",
Style::Wedged => "wedged",
}
}
}
// There is a tension in the design of the labelling API.
//
// For example, I considered making a `Labeller<T>` trait that
// provides labels for `T`, and then making the graph type `G`
// implement `Labeller<Node>` and `Labeller<Edge>`. However, this is
// not possible without functional dependencies. (One could work
// around that, but I did not explore that avenue heavily.)
//
// Another approach that I actually used for a while was to make a
// `Label<Context>` trait that is implemented by the client-specific
// Node and Edge types (as well as an implementation on Graph itself
// for the overall name for the graph). The main disadvantage of this
// second approach (compared to having the `G` type parameter
// implement a Labelling service) that I have encountered is that it
// makes it impossible to use types outside of the current crate
// directly as Nodes/Edges; you need to wrap them in newtype'd
// structs. See e.g. the `No` and `Ed` structs in the examples. (In
// practice clients using a graph in some other crate would need to
// provide some sort of adapter shim over the graph anyway to
// interface with this library).
//
// Another approach would be to make a single `Labeller<N,E>` trait
// that provides three methods (graph_label, node_label, edge_label),
// and then make `G` implement `Labeller<N,E>`. At first this did not
// appeal to me, since I had thought I would need separate methods on
// each data variant for dot-internal identifiers versus user-visible
// labels. However, the identifier/label distinction only arises for
// nodes; graphs themselves only have identifiers, and edges only have
// labels.
//
// So in the end I decided to use the third approach described above.
/// `Id` is a Graphviz `ID`.
pub struct Id<'a> {
name: Cow<'a, str>,
}
impl<'a> Id<'a> {
/// Creates an `Id` named `name`.
///
/// The caller must ensure that the input conforms to an
/// identifier format: it must be a non-empty string made up of
/// alphanumeric or underscore characters, not beginning with a
/// digit (i.e. the regular expression `[a-zA-Z_][a-zA-Z_0-9]*`).
///
/// (Note: this format is a strict subset of the `ID` format
/// defined by the DOT language. This function may change in the
/// future to accept a broader subset, or the entirety, of DOT's
/// `ID` format.)
///
/// Passing an invalid string (containing spaces, brackets,
/// quotes, ...) will return an empty `Err` value.
pub fn new<Name: Into<Cow<'a, str>>>(name: Name) -> Result<Id<'a>, ()> {
let name = name.into();
{
let mut chars = name.chars();
match chars.next() {
Some(c) if is_letter_or_underscore(c) => {}
_ => return Err(()),
}
if !chars.all(is_constituent) {
return Err(())
}
}
return Ok(Id{ name: name });
fn is_letter_or_underscore(c: char) -> bool {
in_range('a', c, 'z') || in_range('A', c, 'Z') || c == '_'
}
fn is_constituent(c: char) -> bool {
is_letter_or_underscore(c) || in_range('0', c, '9')
}
fn in_range(low: char, c: char, high: char) -> bool {
low as usize <= c as usize && c as usize <= high as usize
}
}
pub fn as_slice(&'a self) -> &'a str {
&*self.name
}
pub fn name(self) -> Cow<'a, str> {
self.name
}
}
/// Each instance of a type that implements `Label<C>` maps to a
/// unique identifier with respect to `C`, which is used to identify
/// it in the generated .dot file. They can also provide more
/// elaborate (and non-unique) label text that is used in the graphviz
/// rendered output.
/// The graph instance is responsible for providing the DOT compatible
/// identifiers for the nodes and (optionally) rendered labels for the nodes and
/// edges, as well as an identifier for the graph itself.
pub trait Labeller<'a,N,E> {
/// Must return a DOT compatible identifier naming the graph.
fn graph_id(&'a self) -> Id<'a>;
/// Maps `n` to a unique identifier with respect to `self`. The
/// implementer is responsible for ensuring that the returned name
/// is a valid DOT identifier.
fn node_id(&'a self, n: &N) -> Id<'a>;
/// Maps `n` to one of the [graphviz `shape` names][1]. If `None`
/// is returned, no `shape` attribute is specified.
///
/// [1]: http://www.graphviz.org/content/node-shapes
fn node_shape(&'a self, _node: &N) -> Option<LabelText<'a>> {
None
}
/// Maps `n` to a label that will be used in the rendered output.
/// The label need not be unique, and may be the empty string; the
/// default is just the output from `node_id`.
fn node_label(&'a self, n: &N) -> LabelText<'a> {
LabelStr(self.node_id(n).name())
}
/// Maps `e` to a label that will be used in the rendered output.
/// The label need not be unique, and may be the empty string; the
/// default is in fact the empty string.
fn edge_label(&'a self, e: &E) -> LabelText<'a> {
let _ignored = e;
LabelStr("".into())
}
/// Maps `n` to a style that will be used in the rendered output.
fn node_style(&'a self, _n: &N) -> Style {
Style::None
}
/// Maps `n` to one of the [graphviz `color` names][1]. If `None`
/// is returned, no `color` attribute is specified.
///
/// [1]: https://graphviz.gitlab.io/_pages/doc/info/colors.html
fn node_color(&'a self, _node: &N) -> Option<LabelText<'a>> {
None
}
/// Maps `e` to arrow style that will be used on the end of an edge.
/// Defaults to default arrow style.
fn edge_end_arrow(&'a self, _e: &E) -> Arrow {
Arrow::default()
}
/// Maps `e` to arrow style that will be used on the end of an edge.
/// Defaults to default arrow style.
fn edge_start_arrow(&'a self, _e: &E) -> Arrow {
Arrow::default()
}
/// Maps `e` to a style that will be used in the rendered output.
fn edge_style(&'a self, _e: &E) -> Style {
Style::None
}
/// Maps `e` to one of the [graphviz `color` names][1]. If `None`
/// is returned, no `color` attribute is specified.
///
/// [1]: https://graphviz.gitlab.io/_pages/doc/info/colors.html
fn edge_color(&'a self, _e: &E) -> Option<LabelText<'a>> {
None
}
/// The kind of graph, defaults to `Kind::Digraph`.
#[inline]
fn kind(&self) -> Kind {
Kind::Digraph
}
}
/// Escape tags in such a way that it is suitable for inclusion in a
/// Graphviz HTML label.
pub fn escape_html(s: &str) -> String {
s
.replace("&", "&amp;")
.replace("\"", "&quot;")
.replace("<", "&lt;")
.replace(">", "&gt;")
}
impl<'a> LabelText<'a> {
pub fn label<S:Into<Cow<'a, str>>>(s: S) -> LabelText<'a> {
LabelStr(s.into())
}
pub fn escaped<S:Into<Cow<'a, str>>>(s: S) -> LabelText<'a> {
EscStr(s.into())
}
pub fn html<S: Into<Cow<'a, str>>>(s: S) -> LabelText<'a> {
HtmlStr(s.into())
}
fn escape_char<F>(c: char, mut f: F)
where F: FnMut(char)
{
match c {
// not escaping \\, since Graphviz escString needs to
// interpret backslashes; see EscStr above.
'\\' => f(c),
_ => for c in c.escape_default() {
f(c)
},
}
}
fn escape_str(s: &str) -> String {
let mut out = String::with_capacity(s.len());
for c in s.chars() {
LabelText::escape_char(c, |c| out.push(c));
}
out
}
fn escape_default(s: &str) -> String {
s.chars().flat_map(|c| c.escape_default()).collect()
}
/// Renders text as string suitable for a label in a .dot file.
/// This includes quotes or suitable delimeters.
pub fn to_dot_string(&self) -> String {
match self {
&LabelStr(ref s) => format!("\"{}\"", LabelText::escape_default(s)),
&EscStr(ref s) => format!("\"{}\"", LabelText::escape_str(&s[..])),
&HtmlStr(ref s) => format!("<{}>", s),
}
}
/// Decomposes content into string suitable for making EscStr that
/// yields same content as self. The result obeys the law
/// render(`lt`) == render(`EscStr(lt.pre_escaped_content())`) for
/// all `lt: LabelText`.
fn pre_escaped_content(self) -> Cow<'a, str> {
match self {
EscStr(s) => s,
LabelStr(s) => if s.contains('\\') {
LabelText::escape_default(&*s).into()
} else {
s
},
HtmlStr(s) => s,
}
}
/// Puts `prefix` on a line above this label, with a blank line separator.
pub fn prefix_line(self, prefix: LabelText) -> LabelText<'static> {
prefix.suffix_line(self)
}
/// Puts `suffix` on a line below this label, with a blank line separator.
pub fn suffix_line(self, suffix: LabelText) -> LabelText<'static> {
let mut prefix = self.pre_escaped_content().into_owned();
let suffix = suffix.pre_escaped_content();
prefix.push_str(r"\n\n");
prefix.push_str(&suffix[..]);
EscStr(prefix.into())
}
}
/// This structure holds all information that can describe an arrow connected to
/// either start or end of an edge.
#[derive(Clone, Hash, PartialEq, Eq)]
pub struct Arrow {
pub arrows: Vec<ArrowShape>,
}
use self::ArrowShape::*;
impl Arrow {
/// Return `true` if this is a default arrow.
fn is_default(&self) -> bool {
self.arrows.is_empty()
}
/// Arrow constructor which returns a default arrow
pub fn default() -> Arrow {
Arrow {
arrows: vec![],
}
}
/// Arrow constructor which returns an empty arrow
pub fn none() -> Arrow {
Arrow {
arrows: vec![NoArrow],
}
}
/// Arrow constructor which returns a regular triangle arrow, without modifiers
pub fn normal() -> Arrow {
Arrow {
arrows: vec![ArrowShape::normal()]
}
}
/// Arrow constructor which returns an arrow created by a given ArrowShape.
pub fn from_arrow(arrow: ArrowShape) -> Arrow {
Arrow {
arrows: vec![arrow],
}
}
/// Function which converts given arrow into a renderable form.
pub fn to_dot_string(&self) -> String {
let mut cow = String::new();
for arrow in &self.arrows {
cow.push_str(&arrow.to_dot_string());
};
cow
}
}
impl Into<Arrow> for [ArrowShape; 2] {
fn into(self) -> Arrow {
Arrow {
arrows: vec![self[0], self[1]],
}
}
}
impl Into<Arrow> for [ArrowShape; 3] {
fn into(self) -> Arrow {
Arrow {
arrows: vec![self[0], self[1], self[2]],
}
}
}
impl Into<Arrow> for [ArrowShape; 4] {
fn into(self) -> Arrow {
Arrow {
arrows: vec![self[0], self[1], self[2], self[3]],
}
}
}
/// Arrow modifier that determines if the shape is empty or filled.
#[derive(Clone, Copy, Hash, PartialEq, Eq)]
pub enum Fill {
Open,
Filled,
}
impl Fill {
pub fn as_slice(self) -> &'static str {
match self {
Fill::Open => "o",
Fill::Filled => "",
}
}
}
/// Arrow modifier that determines if the shape is clipped.
/// For example `Side::Left` means only left side is visible.
#[derive(Clone, Copy, Hash, PartialEq, Eq)]
pub enum Side {
Left,
Right,
Both,
}
impl Side {
pub fn as_slice(self) -> &'static str {
match self {
Side::Left => "l",
Side::Right => "r",
Side::Both => "",
}
}
}
/// This enumeration represents all possible arrow edge
/// as defined in [grapviz documentation](http://www.graphviz.org/content/arrow-shapes).
#[derive(Clone, Copy, Hash, PartialEq, Eq)]
pub enum ArrowShape {
/// No arrow will be displayed
NoArrow,
/// Arrow that ends in a triangle. Basically a normal arrow.
/// NOTE: there is error in official documentation, this supports both fill and side clipping
Normal(Fill, Side),
/// Arrow ending in a small square box
Box(Fill, Side),
/// Arrow ending in a three branching lines also called crow's foot
Crow(Side),
/// Arrow ending in a curve
Curve(Side),
/// Arrow ending in an inverted curve
ICurve(Fill, Side),
/// Arrow ending in an diamond shaped rectangular shape.
Diamond(Fill, Side),
/// Arrow ending in a circle.
Dot(Fill),
/// Arrow ending in an inverted triangle.
Inv(Fill, Side),
/// Arrow ending with a T shaped arrow.
Tee(Side),
/// Arrow ending with a V shaped arrow.
Vee(Side),
}
impl ArrowShape {
/// Constructor which returns no arrow.
pub fn none() -> ArrowShape {
ArrowShape::NoArrow
}
/// Constructor which returns normal arrow.
pub fn normal() -> ArrowShape {
ArrowShape::Normal(Fill::Filled, Side::Both)
}
/// Constructor which returns a regular box arrow.
pub fn boxed() -> ArrowShape {
ArrowShape::Box(Fill::Filled, Side::Both)
}
/// Constructor which returns a regular crow arrow.
pub fn crow() -> ArrowShape {
ArrowShape::Crow(Side::Both)
}
/// Constructor which returns a regular curve arrow.
pub fn curve() -> ArrowShape {
ArrowShape::Curve(Side::Both)
}
/// Constructor which returns an inverted curve arrow.
pub fn icurve() -> ArrowShape {
ArrowShape::ICurve(Fill::Filled, Side::Both)
}
/// Constructor which returns a diamond arrow.
pub fn diamond() -> ArrowShape {
ArrowShape::Diamond(Fill::Filled, Side::Both)
}
/// Constructor which returns a circle shaped arrow.
pub fn dot() -> ArrowShape {
ArrowShape::Diamond(Fill::Filled, Side::Both)
}
/// Constructor which returns an inverted triangle arrow.
pub fn inv() -> ArrowShape {
ArrowShape::Inv(Fill::Filled, Side::Both)
}
/// Constructor which returns a T shaped arrow.
pub fn tee() -> ArrowShape {
ArrowShape::Tee(Side::Both)
}
/// Constructor which returns a V shaped arrow.
pub fn vee() -> ArrowShape {
ArrowShape::Vee(Side::Both)
}
/// Function which renders given ArrowShape into a String for displaying.
pub fn to_dot_string(&self) -> String {
let mut res = String::new();
match *self {
Box(fill, side) | ICurve(fill, side)| Diamond(fill, side) |
Inv(fill, side) | Normal(fill, side)=> {
res.push_str(fill.as_slice());
match side {
Side::Left | Side::Right => res.push_str(side.as_slice()),
Side::Both => {},
};
},
Dot(fill) => res.push_str(fill.as_slice()),
Crow(side) | Curve(side) | Tee(side)
| Vee(side) => {
match side {
Side::Left | Side::Right => res.push_str(side.as_slice()),
Side::Both => {},
}
}
NoArrow => {},
};
match *self {
NoArrow => res.push_str("none"),
Normal(_, _) => res.push_str("normal"),
Box(_, _) => res.push_str("box"),
Crow(_) => res.push_str("crow"),
Curve(_) => res.push_str("curve"),
ICurve(_, _) => res.push_str("icurve"),
Diamond(_, _) => res.push_str("diamond"),
Dot(_) => res.push_str("dot"),
Inv(_, _) => res.push_str("inv"),
Tee(_) => res.push_str("tee"),
Vee(_) => res.push_str("vee"),
};
res
}
}
pub type Nodes<'a,N> = Cow<'a,[N]>;
pub type Edges<'a,E> = Cow<'a,[E]>;
/// Graph kind determines if `digraph` or `graph` is used as keyword
/// for the graph.
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum Kind {
Digraph,
Graph,
}
impl Kind {
/// The keyword to use to introduce the graph.
/// Determines which edge syntax must be used, and default style.
fn keyword(&self) -> &'static str {
match *self {
Kind::Digraph => "digraph",
Kind::Graph => "graph"
}
}
/// The edgeop syntax to use for this graph kind.
fn edgeop(&self) -> &'static str {
match *self {
Kind::Digraph => "->",
Kind::Graph => "--",
}
}
}
// (The type parameters in GraphWalk should be associated items,
// when/if Rust supports such.)
/// GraphWalk is an abstraction over a graph = (nodes,edges)
/// made up of node handles `N` and edge handles `E`, where each `E`
/// can be mapped to its source and target nodes.
///
/// The lifetime parameter `'a` is exposed in this trait (rather than
/// introduced as a generic parameter on each method declaration) so
/// that a client impl can choose `N` and `E` that have substructure
/// that is bound by the self lifetime `'a`.
///
/// The `nodes` and `edges` method each return instantiations of
/// `Cow<[T]>` to leave implementers the freedom to create
/// entirely new vectors or to pass back slices into internally owned
/// vectors.
pub trait GraphWalk<'a, N: Clone, E: Clone> {
/// Returns all the nodes in this graph.
fn nodes(&'a self) -> Nodes<'a, N>;
/// Returns all of the edges in this graph.
fn edges(&'a self) -> Edges<'a, E>;
/// The source node for `edge`.
fn source(&'a self, edge: &E) -> N;
/// The target node for `edge`.
fn target(&'a self, edge: &E) -> N;
}
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum RenderOption {
NoEdgeLabels,
NoNodeLabels,
NoEdgeStyles,
NoEdgeColors,
NoNodeStyles,
NoNodeColors,
NoArrows,
}
/// Returns vec holding all the default render options.
pub fn default_options() -> Vec<RenderOption> {
vec![]
}
/// Renders graph `g` into the writer `w` in DOT syntax.
/// (Simple wrapper around `render_opts` that passes a default set of options.)
pub fn render<'a,
N: Clone + 'a,
E: Clone + 'a,
G: Labeller<'a, N, E> + GraphWalk<'a, N, E>,
W: Write>
(g: &'a G,
w: &mut W)
-> io::Result<()> {
render_opts(g, w, &[])
}
/// Renders graph `g` into the writer `w` in DOT syntax.
/// (Main entry point for the library.)
pub fn render_opts<'a,
N: Clone + 'a,
E: Clone + 'a,
G: Labeller<'a, N, E> + GraphWalk<'a, N, E>,
W: Write>
(g: &'a G,
w: &mut W,
options: &[RenderOption])
-> io::Result<()> {
fn writeln<W: Write>(w: &mut W, arg: &[&str]) -> io::Result<()> {
for &s in arg {
try!(w.write_all(s.as_bytes()));
}
write!(w, "\n")
}
fn indent<W: Write>(w: &mut W) -> io::Result<()> {
w.write_all(b" ")
}
try!(writeln(w, &[g.kind().keyword(), " ", g.graph_id().as_slice(), " {"]));
for n in g.nodes().iter() {
let colorstring;
try!(indent(w));
let id = g.node_id(n);
let escaped = &g.node_label(n).to_dot_string();
let shape;
let mut text = vec![id.as_slice()];
if !options.contains(&RenderOption::NoNodeLabels) {
text.push("[label=");
text.push(escaped);
text.push("]");
}
let style = g.node_style(n);
if !options.contains(&RenderOption::NoNodeStyles) && style != Style::None {
text.push("[style=\"");
text.push(style.as_slice());
text.push("\"]");
}
let color = g.node_color(n);
if !options.contains(&RenderOption::NoNodeColors) {
if let Some(c) = color {
colorstring = c.to_dot_string();
text.push("[color=");
text.push(&colorstring);
text.push("]");
}
}
if let Some(s) = g.node_shape(n) {
shape = s.to_dot_string();
text.push("[shape=");
text.push(&shape);
text.push("]");
}
text.push(";");
try!(writeln(w, &text));
}
for e in g.edges().iter() {
let colorstring;
let escaped_label = &g.edge_label(e).to_dot_string();
let start_arrow = g.edge_start_arrow(e);
let end_arrow = g.edge_end_arrow(e);
let start_arrow_s = start_arrow.to_dot_string();
let end_arrow_s = end_arrow.to_dot_string();
try!(indent(w));
let source = g.source(e);
let target = g.target(e);
let source_id = g.node_id(&source);
let target_id = g.node_id(&target);
let mut text = vec![source_id.as_slice(), " ",
g.kind().edgeop(), " ",
target_id.as_slice()];
if !options.contains(&RenderOption::NoEdgeLabels) {
text.push("[label=");
text.push(escaped_label);
text.push("]");
}
let style = g.edge_style(e);
if !options.contains(&RenderOption::NoEdgeStyles) && style != Style::None {
text.push("[style=\"");
text.push(style.as_slice());
text.push("\"]");
}
let color = g.edge_color(e);
if !options.contains(&RenderOption::NoEdgeColors) {
if let Some(c) = color {
colorstring = c.to_dot_string();
text.push("[color=");
text.push(&colorstring);
text.push("]");
}
}
if !options.contains(&RenderOption::NoArrows) &&
(!start_arrow.is_default() || !end_arrow.is_default()) {
text.push("[");
if !end_arrow.is_default() {
text.push("arrowhead=\"");
text.push(&end_arrow_s);
text.push("\"");
}
if !start_arrow.is_default() {
text.push(" dir=\"both\" arrowtail=\"");
text.push(&start_arrow_s);
text.push("\"");
}
text.push("]");
}
text.push(";");
try!(writeln(w, &text));
}
writeln(w, &["}"])
}
#[cfg(test)]
mod tests {
use self::NodeLabels::*;
use super::{Id, Labeller, Nodes, Edges, GraphWalk, render, Style, Kind};
use super::LabelText::{self, LabelStr, EscStr, HtmlStr};
use super::{Arrow, ArrowShape, Side};
use std::io;
use std::io::prelude::*;
/// each node is an index in a vector in the graph.
type Node = usize;
struct Edge {
from: usize,
to: usize,
label: &'static str,
style: Style,
start_arrow: Arrow,
end_arrow: Arrow,
color: Option<&'static str>,
}
fn edge(from: usize, to: usize, label: &'static str, style: Style, color: Option<&'static str>) -> Edge {
Edge {
from: from,
to: to,
label: label,
style: style,
start_arrow: Arrow::default(),
end_arrow: Arrow::default(),
color: color,
}
}
fn edge_with_arrows(from: usize, to: usize, label: &'static str, style:Style,
start_arrow: Arrow, end_arrow: Arrow, color: Option<&'static str>) -> Edge {
Edge {
from: from,
to: to,
label: label,
style: style,
start_arrow: start_arrow,
end_arrow: end_arrow,
color: color,
}
}
struct LabelledGraph {
/// The name for this graph. Used for labelling generated `digraph`.
name: &'static str,
/// Each node is an index into `node_labels`; these labels are
/// used as the label text for each node. (The node *names*,
/// which are unique identifiers, are derived from their index
/// in this array.)
///
/// If a node maps to None here, then just use its name as its
/// text.
node_labels: Vec<Option<&'static str>>,
node_styles: Vec<Style>,
/// Each edge relates a from-index to a to-index along with a
/// label; `edges` collects them.
edges: Vec<Edge>,
}
// A simple wrapper around LabelledGraph that forces the labels to
// be emitted as EscStr.
struct LabelledGraphWithEscStrs {
graph: LabelledGraph,
}
enum NodeLabels<L> {
AllNodesLabelled(Vec<L>),
UnlabelledNodes(usize),
SomeNodesLabelled(Vec<Option<L>>),
}
type Trivial = NodeLabels<&'static str>;
impl NodeLabels<&'static str> {
fn into_opt_strs(self) -> Vec<Option<&'static str>> {
match self {
UnlabelledNodes(len) => vec![None; len],
AllNodesLabelled(lbls) => lbls.into_iter().map(|l| Some(l)).collect(),
SomeNodesLabelled(lbls) => lbls.into_iter().collect(),
}
}
fn len(&self) -> usize {
match self {
&UnlabelledNodes(len) => len,
&AllNodesLabelled(ref lbls) => lbls.len(),
&SomeNodesLabelled(ref lbls) => lbls.len(),
}
}
}
impl LabelledGraph {
fn new(name: &'static str,
node_labels: Trivial,
edges: Vec<Edge>,
node_styles: Option<Vec<Style>>)
-> LabelledGraph {
let count = node_labels.len();
LabelledGraph {
name: name,
node_labels: node_labels.into_opt_strs(),
edges: edges,
node_styles: match node_styles {
Some(nodes) => nodes,
None => vec![Style::None; count],
},
}
}
}
impl LabelledGraphWithEscStrs {
fn new(name: &'static str,
node_labels: Trivial,
edges: Vec<Edge>)
-> LabelledGraphWithEscStrs {
LabelledGraphWithEscStrs { graph: LabelledGraph::new(name, node_labels, edges, None) }
}
}
fn id_name<'a>(n: &Node) -> Id<'a> {
Id::new(format!("N{}", *n)).unwrap()
}
impl<'a> Labeller<'a, Node, &'a Edge> for LabelledGraph {
fn graph_id(&'a self) -> Id<'a> {
Id::new(&self.name[..]).unwrap()
}
fn node_id(&'a self, n: &Node) -> Id<'a> {
id_name(n)
}
fn node_label(&'a self, n: &Node) -> LabelText<'a> {
match self.node_labels[*n] {
Some(ref l) => LabelStr((*l).into()),
None => LabelStr(id_name(n).name()),
}
}
fn edge_label(&'a self, e: &&'a Edge) -> LabelText<'a> {
LabelStr(e.label.into())
}
fn node_style(&'a self, n: &Node) -> Style {
self.node_styles[*n]
}
fn edge_style(&'a self, e: &&'a Edge) -> Style {
e.style
}
fn edge_color(&'a self, e: &&'a Edge) -> Option<LabelText<'a>>
{
match e.color {
Some(l) => {
Some(LabelStr((*l).into()))
},
None => None,
}
}
fn edge_end_arrow(&'a self, e: &&'a Edge) -> Arrow {
e.end_arrow.clone()
}
fn edge_start_arrow(&'a self, e: &&'a Edge) -> Arrow {
e.start_arrow.clone()
}
}
impl<'a> Labeller<'a, Node, &'a Edge> for LabelledGraphWithEscStrs {
fn graph_id(&'a self) -> Id<'a> {
self.graph.graph_id()
}
fn node_id(&'a self, n: &Node) -> Id<'a> {
self.graph.node_id(n)
}
fn node_label(&'a self, n: &Node) -> LabelText<'a> {
match self.graph.node_label(n) {
LabelStr(s) | EscStr(s) | HtmlStr(s) => EscStr(s),
}
}
fn node_color(&'a self, n: &Node) -> Option<LabelText<'a>> {
match self.graph.node_color(n) {
Some(LabelStr(s)) | Some(EscStr(s)) | Some(HtmlStr(s)) => Some(EscStr(s)),
None => None,
}
}
fn edge_label(&'a self, e: &&'a Edge) -> LabelText<'a> {
match self.graph.edge_label(e) {
LabelStr(s) | EscStr(s) | HtmlStr(s) => EscStr(s),
}
}
fn edge_color(&'a self, e: &&'a Edge) -> Option<LabelText<'a>> {
match self.graph.edge_color(e) {
Some(LabelStr(s)) | Some(EscStr(s)) | Some(HtmlStr(s)) => Some(EscStr(s)),
None => None,
}
}
}
impl<'a> GraphWalk<'a, Node, &'a Edge> for LabelledGraph {
fn nodes(&'a self) -> Nodes<'a, Node> {
(0..self.node_labels.len()).collect()
}
fn edges(&'a self) -> Edges<'a, &'a Edge> {
self.edges.iter().collect()
}
fn source(&'a self, edge: &&'a Edge) -> Node {
edge.from
}
fn target(&'a self, edge: &&'a Edge) -> Node {
edge.to
}
}
impl<'a> GraphWalk<'a, Node, &'a Edge> for LabelledGraphWithEscStrs {
fn nodes(&'a self) -> Nodes<'a, Node> {
self.graph.nodes()
}
fn edges(&'a self) -> Edges<'a, &'a Edge> {
self.graph.edges()
}
fn source(&'a self, edge: &&'a Edge) -> Node {
edge.from
}
fn target(&'a self, edge: &&'a Edge) -> Node {
edge.to
}
}
fn test_input(g: LabelledGraph) -> io::Result<String> {
let mut writer = Vec::new();
render(&g, &mut writer).unwrap();
let mut s = String::new();
try!(Read::read_to_string(&mut &*writer, &mut s));
Ok(s)
}
// All of the tests use raw-strings as the format for the expected outputs,
// so that you can cut-and-paste the content into a .dot file yourself to
// see what the graphviz visualizer would produce.
#[test]
fn empty_graph() {
let labels: Trivial = UnlabelledNodes(0);
let r = test_input(LabelledGraph::new("empty_graph", labels, vec![], None));
assert_eq!(r.unwrap(),
r#"digraph empty_graph {
}
"#);
}
#[test]
fn single_node() {
let labels: Trivial = UnlabelledNodes(1);
let r = test_input(LabelledGraph::new("single_node", labels, vec![], None));
assert_eq!(r.unwrap(),
r#"digraph single_node {
N0[label="N0"];
}
"#);
}
#[test]
fn single_node_with_style() {
let labels: Trivial = UnlabelledNodes(1);
let styles = Some(vec![Style::Dashed]);
let r = test_input(LabelledGraph::new("single_node", labels, vec![], styles));
assert_eq!(r.unwrap(),
r#"digraph single_node {
N0[label="N0"][style="dashed"];
}
"#);
}
#[test]
fn single_edge() {
let labels: Trivial = UnlabelledNodes(2);
let result = test_input(LabelledGraph::new("single_edge",
labels,
vec![edge(0, 1, "E", Style::None, None)],
None));
assert_eq!(result.unwrap(),
r#"digraph single_edge {
N0[label="N0"];
N1[label="N1"];
N0 -> N1[label="E"];
}
"#);
}
#[test]
fn single_edge_with_style() {
let labels: Trivial = UnlabelledNodes(2);
let result = test_input(LabelledGraph::new("single_edge",
labels,
vec![edge(0, 1, "E", Style::Bold, Some("red"))],
None));
assert_eq!(result.unwrap(),
r#"digraph single_edge {
N0[label="N0"];
N1[label="N1"];
N0 -> N1[label="E"][style="bold"][color="red"];
}
"#);
}
#[test]
fn test_some_labelled() {
let labels: Trivial = SomeNodesLabelled(vec![Some("A"), None]);
let styles = Some(vec![Style::None, Style::Dotted]);
let result = test_input(LabelledGraph::new("test_some_labelled",
labels,
vec![edge(0, 1, "A-1", Style::None, None)],
styles));
assert_eq!(result.unwrap(),
r#"digraph test_some_labelled {
N0[label="A"];
N1[label="N1"][style="dotted"];
N0 -> N1[label="A-1"];
}
"#);
}
#[test]
fn single_cyclic_node() {
let labels: Trivial = UnlabelledNodes(1);
let r = test_input(LabelledGraph::new("single_cyclic_node",
labels,
vec![edge(0, 0, "E", Style::None, None)],
None));
assert_eq!(r.unwrap(),
r#"digraph single_cyclic_node {
N0[label="N0"];
N0 -> N0[label="E"];
}
"#);
}
#[test]
fn hasse_diagram() {
let labels = AllNodesLabelled(vec!("{x,y}", "{x}", "{y}", "{}"));
let r = test_input(LabelledGraph::new("hasse_diagram",
labels,
vec![edge(0, 1, "", Style::None, Some("green")),
edge(0, 2, "", Style::None, Some("blue")),
edge(1, 3, "", Style::None, Some("red")),
edge(2, 3, "", Style::None, Some("black"))],
None));
assert_eq!(r.unwrap(),
r#"digraph hasse_diagram {
N0[label="{x,y}"];
N1[label="{x}"];
N2[label="{y}"];
N3[label="{}"];
N0 -> N1[label=""][color="green"];
N0 -> N2[label=""][color="blue"];
N1 -> N3[label=""][color="red"];
N2 -> N3[label=""][color="black"];
}
"#);
}
#[test]
fn left_aligned_text() {
let labels = AllNodesLabelled(vec!(
"if test {\
\\l branch1\
\\l} else {\
\\l branch2\
\\l}\
\\lafterward\
\\l",
"branch1",
"branch2",
"afterward"));
let mut writer = Vec::new();
let g = LabelledGraphWithEscStrs::new("syntax_tree",
labels,
vec![edge(0, 1, "then", Style::None, None),
edge(0, 2, "else", Style::None, None),
edge(1, 3, ";", Style::None, None),
edge(2, 3, ";", Style::None, None)]);
render(&g, &mut writer).unwrap();
let mut r = String::new();
Read::read_to_string(&mut &*writer, &mut r).unwrap();
assert_eq!(r,
r#"digraph syntax_tree {
N0[label="if test {\l branch1\l} else {\l branch2\l}\lafterward\l"];
N1[label="branch1"];
N2[label="branch2"];
N3[label="afterward"];
N0 -> N1[label="then"];
N0 -> N2[label="else"];
N1 -> N3[label=";"];
N2 -> N3[label=";"];
}
"#);
}
#[test]
fn simple_id_construction() {
let id1 = Id::new("hello");
match id1 {
Ok(_) => {}
Err(..) => panic!("'hello' is not a valid value for id anymore"),
}
}
#[test]
fn test_some_arrow() {
let labels: Trivial = SomeNodesLabelled(vec![Some("A"), None]);
let styles = Some(vec![Style::None, Style::Dotted]);
let start = Arrow::default();
let end = Arrow::from_arrow(ArrowShape::crow());
let result = test_input(LabelledGraph::new("test_some_labelled",
labels,
vec![edge_with_arrows(0, 1, "A-1", Style::None, start, end, None)],
styles));
assert_eq!(result.unwrap(),
r#"digraph test_some_labelled {
N0[label="A"];
N1[label="N1"][style="dotted"];
N0 -> N1[label="A-1"][arrowhead="crow"];
}
"#);
}
#[test]
fn test_some_arrows() {
let labels: Trivial = SomeNodesLabelled(vec![Some("A"), None]);
let styles = Some(vec![Style::None, Style::Dotted]);
let start = Arrow::from_arrow(ArrowShape::tee());
let end = Arrow::from_arrow(ArrowShape::Crow(Side::Left));
let result = test_input(LabelledGraph::new("test_some_labelled",
labels,
vec![edge_with_arrows(0, 1, "A-1", Style::None, start, end, None)],
styles));
assert_eq!(result.unwrap(),
r#"digraph test_some_labelled {
N0[label="A"];
N1[label="N1"][style="dotted"];
N0 -> N1[label="A-1"][arrowhead="lcrow" dir="both" arrowtail="tee"];
}
"#);
}
#[test]
fn invisible() {
let labels: Trivial = UnlabelledNodes(1);
let r = test_input(LabelledGraph::new("single_cyclic_node",
labels,
vec![edge(0, 0, "E", Style::Invisible, None)],
Some(vec![Style::Invisible])));
assert_eq!(r.unwrap(),
r#"digraph single_cyclic_node {
N0[label="N0"][style="invis"];
N0 -> N0[label="E"][style="invis"];
}
"#);
}
#[test]
fn badly_formatted_id() {
let id2 = Id::new("Weird { struct : ure } !!!");
match id2 {
Ok(_) => panic!("graphviz id suddenly allows spaces, brackets and stuff"),
Err(..) => {}
}
}
type SimpleEdge = (Node, Node);
struct DefaultStyleGraph {
/// The name for this graph. Used for labelling generated graph
name: &'static str,
nodes: usize,
edges: Vec<SimpleEdge>,
kind: Kind,
}
impl DefaultStyleGraph {
fn new(name: &'static str,
nodes: usize,
edges: Vec<SimpleEdge>,
kind: Kind)
-> DefaultStyleGraph {
assert!(!name.is_empty());
DefaultStyleGraph {
name: name,
nodes: nodes,
edges: edges,
kind: kind,
}
}
}
impl<'a> Labeller<'a, Node, &'a SimpleEdge> for DefaultStyleGraph {
fn graph_id(&'a self) -> Id<'a> {
Id::new(&self.name[..]).unwrap()
}
fn node_id(&'a self, n: &Node) -> Id<'a> {
id_name(n)
}
fn kind(&self) -> Kind {
self.kind
}
}
impl<'a> GraphWalk<'a, Node, &'a SimpleEdge> for DefaultStyleGraph {
fn nodes(&'a self) -> Nodes<'a, Node> {
(0..self.nodes).collect()
}
fn edges(&'a self) -> Edges<'a, &'a SimpleEdge> {
self.edges.iter().collect()
}
fn source(&'a self, edge: &&'a SimpleEdge) -> Node {
edge.0
}
fn target(&'a self, edge: &&'a SimpleEdge) -> Node {
edge.1
}
}
fn test_input_default(g: DefaultStyleGraph) -> io::Result<String> {
let mut writer = Vec::new();
render(&g, &mut writer).unwrap();
let mut s = String::new();
try!(Read::read_to_string(&mut &*writer, &mut s));
Ok(s)
}
#[test]
fn default_style_graph() {
let r = test_input_default(
DefaultStyleGraph::new("g", 4,
vec![(0, 1), (0, 2), (1, 3), (2, 3)],
Kind::Graph));
assert_eq!(r.unwrap(),
r#"graph g {
N0[label="N0"];
N1[label="N1"];
N2[label="N2"];
N3[label="N3"];
N0 -- N1[label=""];
N0 -- N2[label=""];
N1 -- N3[label=""];
N2 -- N3[label=""];
}
"#);
}
#[test]
fn default_style_digraph() {
let r = test_input_default(
DefaultStyleGraph::new("di", 4,
vec![(0, 1), (0, 2), (1, 3), (2, 3)],
Kind::Digraph));
assert_eq!(r.unwrap(),
r#"digraph di {
N0[label="N0"];
N1[label="N1"];
N2[label="N2"];
N3[label="N3"];
N0 -> N1[label=""];
N0 -> N2[label=""];
N1 -> N3[label=""];
N2 -> N3[label=""];
}
"#);
}
}