asciidoc-parser 0.19.0

use crate::{HasSpan, tests::prelude::*};

track_file!("ref/asciidoc-lang/docs/modules/directives/pages/conditionals.adoc");

non_normative!(
    r#"
= Conditionals

You can include or exclude lines of text in your document using the following conditional preprocessor directives:

* xref:ifdef-ifndef.adoc#ifdef[ifdef]
* xref:ifdef-ifndef.adoc#ifndef[ifndef]
* xref:ifeval.adoc[ifeval]

"#
);

#[test]
fn condition_determines_inclusion() {
    verifies!(
        r#"
When the processor encounters one of these conditionals, it evaluates the specified condition.
The condition is based on the presence or value of one or more document attributes.
If the condition evaluates to true, the lines the conditional encloses are included.
Otherwise, the lines are skipped.

"#
    );

    // When the condition evaluates to true, the enclosed lines are included.
    let doc = Parser::default().parse(":flag:\n\nifdef::flag[]\nShown.\nendif::[]");
    assert_eq!(rendered_paragraphs(&doc), vec!["Shown."]);

    // Otherwise, the enclosed lines are skipped.
    let doc = Parser::default().parse("ifdef::flag[]\nHidden.\nendif::[]\n\nAfter.");
    assert_eq!(rendered_paragraphs(&doc), vec!["After."]);
}

non_normative!(
    r#"
////
For example, say you want to include a certain section of content only when converting to HTML.
Conditional preprocessor directives make this possible.
You simply check for the presence of the `basebackend-html` attribute using an `ifdef` directive.
Details of this example and more `ifdef` and `ifndef` examples, are described in the following sections.
See xref:ifeval.adoc[] for `ifeval` examples.
////

== Conditional processing

Although a conditional preprocessor directive looks like a block macro, *it's not a macro and therefore isn't processed like one*.
It's a preprocessor directive; it's important to understand the distinction.

include::partial$preprocessor.adoc[]
The conditional preprocessor directives determine which lines to add and which ones to take away based on the condition.

"#
);

#[test]
fn escape_a_conditional_directive() {
    verifies!(
        r#"
== Escape a conditional directive

If you don't want a conditional preprocessor directive to be processed, you must escape it using a backslash.

"#
    );

    // The escaped directive is not processed: the leading backslash is removed
    // and the remainder is emitted literally. This holds even inside a verbatim
    // block because the preprocessor is not aware of the surrounding structure.
    let doc = Parser::default().parse("----\n\\ifdef::just-an-example[]\n----");
    let block = doc.nested_blocks().next().unwrap();
    assert_eq!(block.span().data(), "----\nifdef::just-an-example[]\n----");
}

non_normative!(
    r#"
// NOTE: the following listing uses indentation to prevent the directive from being processed
[source,indent=0]
----
 \ifdef::just-an-example[]
----

Escaping the directive is necessary _even if it appears in a verbatim block_ since it's not aware of the surrounding document structure.
"#
);