improve title extraction

src/constants.rs

@@ -0,0 +1,79 @@
+use std::collections::HashSet;
+
+use once_cell::sync::Lazy;
+use regex::Regex;
+
+pub const DEFAULT_CHAR_THRESHOLD: usize = 500;
+pub static SIBLING_CONTENT: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"/\.( |$)/"#).expect("SIBLING_CONTENT regex"));
+pub static BYLINE: Lazy<Regex> = Lazy::new(|| {
+    Regex::new(r#"/byline|author|dateline|writtenby|p-author/i"#).expect("BYLINE regex")
+});
+pub static NORMALIZE: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"/\s{2,}/g"#).expect("NORMALIZE regex"));
+pub static TOKENIZE: Lazy<Regex> = Lazy::new(|| Regex::new(r#"\W+"#).expect("TOKENIZE regex"));
+pub static UNLIELY_CANDIDATES: Lazy<Regex> = Lazy::new(|| {
+    Regex::new(r#"/-ad-|ai2html|banner|breadcrumbs|combx|comment|community|cover-wrap|disqus|extra|footer|gdpr|header|legends|menu|related|remark|replies|rss|shoutbox|sidebar|skyscraper|social|sponsor|supplemental|ad-break|agegate|pagination|pager|popup|yom-remote/i"#).expect("UNLIELY_CANDIDATES regex")
+});
+pub static OKAY_MAYBE_ITS_A_CANDIDATE: Lazy<Regex> = Lazy::new(|| {
+    Regex::new(r#"/and|article|body|column|content|main|shadow/i"#)
+        .expect("OKAY_MAYBE_ITS_A_CANDIDATE regex")
+});
+pub static HAS_CONTENT: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"/\S$/"#).expect("HAS_CONTENT regex"));
+pub static HASH_URL: Lazy<Regex> = Lazy::new(|| Regex::new(r#"/^#.+/"#).expect("HASH_URL regex"));
+pub static POSITIVE: Lazy<Regex> = Lazy::new(|| {
+    Regex::new(
+        r#"/article|body|content|entry|hentry|h-entry|main|page|pagination|post|text|blog|story/i"#,
+    )
+    .expect("POSITIVE regex")
+});
+pub static NEGATIVE: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"/-ad-|hidden|^hid$| hid$| hid |^hid"#).expect("NEGATIVE regex"));
+
+pub static TITLE_SEPARATOR: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"[-|\\/>»]"#).expect("TITLE_SEPARATOR regex"));
+pub static TITLE_CUT_END: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"(.*)[-|\\/>»] .*"#).expect("TITLE_CUT_END regex"));
+pub static WORD_COUNT: Lazy<Regex> = Lazy::new(|| Regex::new(r#"\s+"#).expect("WORD_COUNT regex"));
+pub static TITLE_CUT_FRONT: Lazy<Regex> =
+    Lazy::new(|| Regex::new(r#"/[^-|\\/>»]*[-|\\/>»](.*)/gi"#).expect("TITLE_CUT_FRONT regex"));
+
+pub const SCORE_ATTR: &str = "content_score";
+pub const MINIMUM_TOPCANDIDATES: usize = 3;
+pub const UNLIKELY_ROLES: &[&str] = &[
+    "menu",
+    "menubar",
+    "complementary",
+    "navigation",
+    "alert",
+    "alertdialog",
+    "dialog",
+];
+
+pub const DEFAULT_TAGS_TO_SCORE: &[&str] =
+    &["SECTION", "H2", "H3", "H4", "H5", "H6", "P", "TD", "PRE"];
+pub static DIV_TO_P_ELEMS: Lazy<HashSet<&'static str>> = Lazy::new(|| {
+    HashSet::from([
+        "BLOCKQUOTE",
+        "DL",
+        "DIV",
+        "IMG",
+        "OL",
+        "P",
+        "PRE",
+        "TABLE",
+        "UL",
+    ])
+});
+
+pub static ALTER_TO_DIV_EXCEPTIONS: Lazy<HashSet<&'static str>> =
+    Lazy::new(|| HashSet::from(["DIV", "ARTICLE", "SECTION", "P"]));
+
+pub const PHRASING_ELEMS: &[&str] = &[
+    // "CANVAS", "IFRAME", "SVG", "VIDEO",
+    "ABBR", "AUDIO", "B", "BDO", "BR", "BUTTON", "CITE", "CODE", "DATA", "DATALIST", "DFN", "EM",
+    "EMBED", "I", "IMG", "INPUT", "KBD", "LABEL", "MARK", "MATH", "METER", "NOSCRIPT", "OBJECT",
+    "OUTPUT", "PROGRESS", "Q", "RUBY", "SAMP", "SCRIPT", "SELECT", "SMALL", "SPAN", "STRONG",
+    "SUB", "SUP", "TEXTAREA", "TIME", "VAR", "WBR",
+];