feat(plugins): extension points, capability consent, async runtime and plugin API 1.0

Rework the plugin system per docs/plugin_plan.md (P0–P8): - Extension-point registry (ide-extension) so new contribution types register without touching the kernel; languages, run detectors, providers, views and UI contributions go through it. - Per-plugin capability consent with a risk-graded ledger; process capabilities are pinned to resolved binary paths and hashes. - Async, actor-per-plugin Wasm runtime with lazy activation, cancellation, events, long-running tasks and idle reclamation. - Plugin host moved into ide-host, shared by local and remote projects. - Distribution: install/package tooling (openidea-plugin bin) and a static market index. - WIT frozen as openidea:[email protected]; Rust SDK with mock host. - Ten official validation plugins under plugins/official.
2026-11-09 11:15:40 +02:00 · 2026-11-04 02:41:46 +08:00
@@ -0,0 +1 @@
+/target
@@ -0,0 +1,333 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
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+name = "anyhow"
+version = "1.0.104"
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+
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+
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+ "foldhash",
+]
+
+[[package]]
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+version = "0.1.0"
+dependencies = [
+ "wit-bindgen",
+]
+
+[[package]]
+name = "openidea-plugin-openidea-string-tools"
+version = "0.1.0"
+dependencies = [
+ "openidea-plugin",
+]
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+ "wit-bindgen-core",
+ "wit-component",
+]
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+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "syn",
+ "wit-bindgen-core",
+ "wit-bindgen-rust",
+]
+
+[[package]]
+name = "wit-component"
+version = "0.262.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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+ "bitflags",
+ "indexmap",
+ "log",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "wasm-encoder",
+ "wasm-metadata",
+ "wasmparser",
+ "wit-parser",
+]
+
+[[package]]
+name = "wit-parser"
+version = "0.262.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "00f0dc051466ffe46787721fca3d088536f158ae400be044f1b1c386ba9397ad"
+dependencies = [
+ "anyhow",
+ "hashbrown",
+ "id-arena",
+ "indexmap",
+ "log",
+ "semver",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "unicode-ident",
+ "wasmparser",
+]
+
+[[package]]
+name = "zmij"
+version = "1.0.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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@@ -0,0 +1,21 @@
+[package]
+name = "openidea-plugin-openidea-string-tools"
+version = "0.1.0"
+edition = "2024"
+publish = false
+
+# A plugin builds on its own (target wasm32-wasip2), outside any IDE workspace.
+[workspace]
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[dependencies]
+openidea-plugin = { path = "../../../sdk/rust/openidea-plugin" }
+
+[profile.release]
+opt-level = "s"
+lto = true
+strip = true
+codegen-units = 1
+panic = "abort"
@@ -0,0 +1,171 @@
+id = "openidea.string-tools"
+name = "String Tools"
+version = "0.1.0"
+description = "Case conversion (camelCase, snake_case, kebab-case…), encoding (Base64, URL, HTML, JSON), line sorting and more, on every selection at once."
+authors = ["OpenIDEA contributors"]
+license = "Apache-2.0"
+change-notes = "0.1.0 — first release: 26 commands in four groups."
+engines.openidea = "^1.0"
+wasm = "dist/plugin.wasm"
+# The commands are declared below, so Find Action and the keymap list them
+# before the code is ever loaded; it loads on the first one run.
+activation = ["on-command:*"]
+
+[capabilities]
+required = ["editor.read", "editor.write"]
+
+[[contributes.commands]]
+id = "camel-case"
+title = "String Tools: To camelCase"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "pascal-case"
+title = "String Tools: To PascalCase"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "snake-case"
+title = "String Tools: To snake_case"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "screaming-snake-case"
+title = "String Tools: To SCREAMING_SNAKE_CASE"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "kebab-case"
+title = "String Tools: To kebab-case"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "dot-case"
+title = "String Tools: To dot.case"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "title-case"
+title = "String Tools: To Title Case"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "upper-case"
+title = "String Tools: To UPPER CASE"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "lower-case"
+title = "String Tools: To lower case"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "toggle-case"
+title = "String Tools: Toggle Case"
+category = "String Tools › Case"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "base64-encode"
+title = "String Tools: Encode Base64"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "base64-decode"
+title = "String Tools: Decode Base64"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "url-encode"
+title = "String Tools: URL-Encode"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "url-decode"
+title = "String Tools: URL-Decode"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "html-escape"
+title = "String Tools: Escape HTML"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "html-unescape"
+title = "String Tools: Unescape HTML"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "json-escape"
+title = "String Tools: Escape as JSON String"
+category = "String Tools › Encode"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "sort-lines"
+title = "String Tools: Sort Lines"
+category = "String Tools › Lines"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "sort-lines-desc"
+title = "String Tools: Sort Lines Descending"
+category = "String Tools › Lines"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "reverse-lines"
+title = "String Tools: Reverse Lines"
+category = "String Tools › Lines"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "unique-lines"
+title = "String Tools: Remove Duplicate Lines"
+category = "String Tools › Lines"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "trim-lines"
+title = "String Tools: Trim Lines"
+category = "String Tools › Lines"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "reverse"
+title = "String Tools: Reverse Text"
+category = "String Tools › Other"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "swap-quotes"
+title = "String Tools: Swap Quotes (' ↔ \")"
+category = "String Tools › Other"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "increment"
+title = "String Tools: Increment Numbers"
+category = "String Tools › Other"
+when = "editorFocus"
+
+[[contributes.commands]]
+id = "decrement"
+title = "String Tools: Decrement Numbers"
+category = "String Tools › Other"
+when = "editorFocus"
@@ -0,0 +1,460 @@
+//! String Tools for OpenIDEA: text transformations on every selection of the
+//! focused editor, applied as one undoable change. An empty selection
+//! (a cursor) works on the word under it; line commands on whole lines.
+
+use openidea_plugin::text::{offset, position};
+use openidea_plugin::{Error, Invocation, Plugin, Range, TextEdit, TextEditor, register_plugin};
+
+#[derive(Default)]
+pub struct StringTools;
+
+impl Plugin for StringTools {
+    fn run_command(&mut self, id: &str, ctx: &Invocation, _arg: Option<&str>) -> Result<Option<String>, String> {
+        let transform = transform(id).ok_or_else(|| format!("unknown command {id}"))?;
+        let editor = ctx.editor().ok_or("String Tools works on the focused editor")?;
+        apply(&editor, transform, lines_command(id)).map_err(|e| e.to_string())?;
+        Ok(None)
+    }
+}
+
+register_plugin!(StringTools);
+
+type Transform = fn(&str) -> String;
+
+fn lines_command(id: &str) -> bool {
+    matches!(id, "sort-lines" | "sort-lines-desc" | "reverse-lines" | "unique-lines" | "trim-lines")
+}
+
+fn transform(id: &str) -> Option<Transform> {
+    Some(match id {
+        "camel-case" => |s| join_words(s, Style::Camel),
+        "pascal-case" => |s| join_words(s, Style::Pascal),
+        "snake-case" => |s| join_words(s, Style::Snake),
+        "screaming-snake-case" => |s| join_words(s, Style::ScreamingSnake),
+        "kebab-case" => |s| join_words(s, Style::Kebab),
+        "dot-case" => |s| join_words(s, Style::Dot),
+        "title-case" => title_case,
+        "upper-case" => |s| s.to_uppercase(),
+        "lower-case" => |s| s.to_lowercase(),
+        "toggle-case" => toggle_case,
+        "base64-encode" => |s| base64_encode(s.as_bytes()),
+        "base64-decode" => {
+            |s| base64_decode(s).map_or_else(|| s.to_owned(), |b| String::from_utf8_lossy(&b).into_owned())
+        }
+        "url-encode" => url_encode,
+        "url-decode" => url_decode,
+        "html-escape" => html_escape,
+        "html-unescape" => html_unescape,
+        "json-escape" => json_escape,
+        "sort-lines" => |s| map_lines(s, |l| l.sort()),
+        "sort-lines-desc" => |s| map_lines(s, |l| l.sort_by(|a, b| b.cmp(a))),
+        "reverse-lines" => |s| map_lines(s, |l| l.reverse()),
+        "unique-lines" => |s| {
+            map_lines(s, |l| {
+                let mut seen = std::collections::HashSet::new();
+                l.retain(|x| seen.insert(x.to_owned()));
+            })
+        },
+        "trim-lines" => |s| s.split('\n').map(str::trim).collect::<Vec<_>>().join("\n"),
+        "reverse" => |s| s.chars().rev().collect(),
+        "swap-quotes" => |s| {
+            s.chars()
+                .map(|c| match c {
+                    '"' => '\'',
+                    '\'' => '"',
+                    c => c,
+                })
+                .collect()
+        },
+        "increment" => |s| step_numbers(s, 1),
+        "decrement" => |s| step_numbers(s, -1),
+        _ => return None,
+    })
+}
+
+/// Replaces each selection with `f(text)`: an empty one expands to the word
+/// under the cursor, or (`lines`) every selection to its whole lines.
+/// Retried once if the user typed meanwhile.
+fn apply(editor: &TextEditor, f: Transform, lines: bool) -> Result<u64, Error> {
+    let selections = editor.selections()?;
+    for _ in 0..2 {
+        let doc = editor.document()?;
+        let mut edits = Vec::with_capacity(selections.len());
+        for r in &selections {
+            let range = if lines { line_range(&doc.text, *r) } else { word_range(&doc.text, *r) };
+            let Some(old) = doc.text_in(range) else { continue };
+            let new = f(old);
+            if new != old {
+                edits.push(TextEdit { range, text: new });
+            }
+        }
+        // Overlapping selections (two cursors in one word) edit once.
+        edits.sort_by_key(|e| e.range);
+        edits.dedup_by(|b, a| b.range.start < a.range.end);
+        match editor.apply_edits(doc.version, &edits) {
+            Err(Error::Stale) => continue,
+            other => return other,
+        }
+    }
+    Err(Error::Stale)
+}
+
+fn word_range(text: &str, r: Range) -> Range {
+    if !r.is_empty() {
+        return r;
+    }
+    let Some(at) = offset(text, r.start) else { return r };
+    let word = |c: char| c.is_alphanumeric() || c == '_' || c == '-' || c == '.';
+    let start = text[..at].char_indices().rev().take_while(|(_, c)| word(*c)).last().map_or(at, |(i, _)| i);
+    let end = text[at..].char_indices().find(|(_, c)| !word(*c)).map_or(text.len(), |(i, _)| at + i);
+    Range::new(position(text, start), position(text, end))
+}
+
+fn line_range(text: &str, r: Range) -> Range {
+    let start = openidea_plugin::Position::new(r.start.line, 0);
+    let end_line = if r.end.character == 0 && r.end.line > r.start.line { r.end.line - 1 } else { r.end.line };
+    let line_end = text.split('\n').nth(end_line as usize).map_or(0, |l| l.encode_utf16().count() as u32);
+    Range::new(start, openidea_plugin::Position::new(end_line, line_end))
+}
+
+#[derive(Clone, Copy)]
+enum Style {
+    Camel,
+    Pascal,
+    Snake,
+    ScreamingSnake,
+    Kebab,
+    Dot,
+}
+
+/// Splits identifiers on separators and case changes: `fooBar_baz-qux` →
+/// [foo, Bar, baz, qux]; `HTTPServer` → [HTTP, Server].
+fn words(s: &str) -> Vec<String> {
+    let chars: Vec<char> = s.chars().collect();
+    let mut out = Vec::new();
+    let mut cur = String::new();
+    for (i, &c) in chars.iter().enumerate() {
+        if !c.is_alphanumeric() {
+            if !cur.is_empty() {
+                out.push(std::mem::take(&mut cur));
+            }
+            continue;
+        }
+        let prev = i.checked_sub(1).map(|j| chars[j]);
+        let next = chars.get(i + 1).copied();
+        let boundary = c.is_uppercase()
+            && prev.is_some_and(|p| {
+                p.is_lowercase() || p.is_ascii_digit() || (p.is_uppercase() && next.is_some_and(char::is_lowercase))
+            });
+        if boundary && !cur.is_empty() {
+            out.push(std::mem::take(&mut cur));
+        }
+        cur.push(c);
+    }
+    if !cur.is_empty() {
+        out.push(cur);
+    }
+    out
+}
+
+fn capitalize(w: &str) -> String {
+    let mut c = w.chars();
+    c.next().map(|f| f.to_uppercase().chain(c.flat_map(char::to_lowercase)).collect()).unwrap_or_default()
+}
+
+fn join_words(s: &str, style: Style) -> String {
+    // Keep surrounding whitespace (a whole-line selection).
+    let lead = &s[..s.len() - s.trim_start().len()];
+    let trail = &s[s.trim_end().len()..];
+    let w = words(s);
+    let body = match style {
+        Style::Camel => {
+            w.iter().enumerate().map(|(i, x)| if i == 0 { x.to_lowercase() } else { capitalize(x) }).collect()
+        }
+        Style::Pascal => w.iter().map(|x| capitalize(x)).collect(),
+        Style::Snake => w.iter().map(|x| x.to_lowercase()).collect::<Vec<_>>().join("_"),
+        Style::ScreamingSnake => w.iter().map(|x| x.to_uppercase()).collect::<Vec<_>>().join("_"),
+        Style::Kebab => w.iter().map(|x| x.to_lowercase()).collect::<Vec<_>>().join("-"),
+        Style::Dot => w.iter().map(|x| x.to_lowercase()).collect::<Vec<_>>().join("."),
+    };
+    if body.is_empty() { s.to_owned() } else { format!("{lead}{body}{trail}") }
+}
+
+fn title_case(s: &str) -> String {
+    let mut out = String::with_capacity(s.len());
+    let mut start = true;
+    for c in s.chars() {
+        if start && c.is_alphabetic() {
+            out.extend(c.to_uppercase());
+            start = false;
+        } else {
+            out.extend(c.to_lowercase());
+            start = c.is_whitespace();
+        }
+    }
+    out
+}
+
+fn toggle_case(s: &str) -> String {
+    s.chars()
+        .flat_map(|c| -> Box<dyn Iterator<Item = char>> {
+            if c.is_uppercase() { Box::new(c.to_lowercase()) } else { Box::new(c.to_uppercase()) }
+        })
+        .collect()
+}
+
+fn map_lines(s: &str, f: impl FnOnce(&mut Vec<&str>)) -> String {
+    let mut lines: Vec<&str> = s.split('\n').collect();
+    f(&mut lines);
+    lines.join("\n")
+}
+
+/// Adds `by` to every integer in `s` (keeping zero padding).
+fn step_numbers(s: &str, by: i64) -> String {
+    let mut out = String::with_capacity(s.len());
+    let chars: Vec<char> = s.chars().collect();
+    let mut i = 0;
+    while i < chars.len() {
+        if chars[i].is_ascii_digit() {
+            let start = i;
+            while i < chars.len() && chars[i].is_ascii_digit() {
+                i += 1;
+            }
+            let neg = start > 0 && chars[start - 1] == '-' && (start < 2 || !chars[start - 2].is_alphanumeric());
+            let digits: String = chars[start..i].iter().collect();
+            match digits.parse::<i64>() {
+                Ok(n) => {
+                    let n = if neg { -n } else { n };
+                    let next = n.saturating_add(by);
+                    if neg {
+                        out.pop(); // the minus sign
+                    }
+                    let width = digits.len();
+                    let text = if next < 0 { format!("-{:0width$}", -next) } else { format!("{next:0width$}") };
+                    out.push_str(&text);
+                }
+                Err(_) => out.push_str(&digits),
+            }
+        } else {
+            out.push(chars[i]);
+            i += 1;
+        }
+    }
+    out
+}
+
+const B64: &[u8; 64] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+fn base64_encode(bytes: &[u8]) -> String {
+    let mut out = String::with_capacity(bytes.len().div_ceil(3) * 4);
+    for chunk in bytes.chunks(3) {
+        let n = chunk.iter().enumerate().fold(0u32, |n, (i, b)| n | u32::from(*b) << (16 - 8 * i));
+        for i in 0..4 {
+            if i <= chunk.len() {
+                out.push(B64[(n >> (18 - 6 * i) & 63) as usize] as char);
+            } else {
+                out.push('=');
+            }
+        }
+    }
+    out
+}
+
+fn base64_decode(s: &str) -> Option<Vec<u8>> {
+    let clean: Vec<u8> = s.bytes().filter(|b| !b.is_ascii_whitespace()).collect();
+    let clean = clean.strip_suffix(b"==").or_else(|| clean.strip_suffix(b"=")).unwrap_or(&clean);
+    let mut out = Vec::with_capacity(clean.len() * 3 / 4);
+    for chunk in clean.chunks(4) {
+        if chunk.len() == 1 {
+            return None;
+        }
+        let mut n = 0u32;
+        for (i, b) in chunk.iter().enumerate() {
+            let v = B64.iter().position(|x| x == b).or_else(|| match b {
+                b'-' => Some(62),
+                b'_' => Some(63),
+                _ => None,
+            })?;
+            n |= (v as u32) << (18 - 6 * i);
+        }
+        for i in 0..chunk.len() - 1 {
+            out.push((n >> (16 - 8 * i)) as u8);
+        }
+    }
+    Some(out)
+}
+
+fn url_encode(s: &str) -> String {
+    s.bytes()
+        .map(|b| match b {
+            b'A'..=b'Z' | b'a'..=b'z' | b'0'..=b'9' | b'-' | b'_' | b'.' | b'~' => (b as char).to_string(),
+            _ => format!("%{b:02X}"),
+        })
+        .collect()
+}
+
+fn url_decode(s: &str) -> String {
+    let bytes = s.as_bytes();
+    let mut out = Vec::with_capacity(bytes.len());
+    let mut i = 0;
+    while i < bytes.len() {
+        let hex = |j: usize| bytes.get(j).and_then(|b| (*b as char).to_digit(16));
+        match bytes[i] {
+            b'%' if hex(i + 1).is_some() && hex(i + 2).is_some() => {
+                out.push((hex(i + 1).unwrap() * 16 + hex(i + 2).unwrap()) as u8);
+                i += 3;
+            }
+            b'+' => {
+                out.push(b' ');
+                i += 1;
+            }
+            b => {
+                out.push(b);
+                i += 1;
+            }
+        }
+    }
+    String::from_utf8_lossy(&out).into_owned()
+}
+
+fn html_escape(s: &str) -> String {
+    let mut out = String::with_capacity(s.len());
+    for c in s.chars() {
+        match c {
+            '&' => out.push_str("&amp;"),
+            '<' => out.push_str("&lt;"),
+            '>' => out.push_str("&gt;"),
+            '"' => out.push_str("&quot;"),
+            '\'' => out.push_str("&#39;"),
+            c => out.push(c),
+        }
+    }
+    out
+}
+
+fn html_unescape(s: &str) -> String {
+    let mut out = String::with_capacity(s.len());
+    let mut rest = s;
+    while let Some(i) = rest.find('&') {
+        out.push_str(&rest[..i]);
+        rest = &rest[i..];
+        let Some(end) = rest[..rest.len().min(12)].find(';') else {
+            out.push('&');
+            rest = &rest[1..];
+            continue;
+        };
+        let entity = &rest[1..end];
+        let decoded = match entity {
+            "amp" => Some('&'),
+            "lt" => Some('<'),
+            "gt" => Some('>'),
+            "quot" => Some('"'),
+            "apos" => Some('\''),
+            "nbsp" => Some('\u{a0}'),
+            e if e.starts_with("#x") || e.starts_with("#X") => {
+                u32::from_str_radix(&e[2..], 16).ok().and_then(char::from_u32)
+            }
+            e if e.starts_with('#') => e[1..].parse().ok().and_then(char::from_u32),
+            _ => None,
+        };
+        match decoded {
+            Some(c) => {
+                out.push(c);
+                rest = &rest[end + 1..];
+            }
+            None => {
+                out.push('&');
+                rest = &rest[1..];
+            }
+        }
+    }
+    out.push_str(rest);
+    out
+}
+
+fn json_escape(s: &str) -> String {
+    let mut out = String::with_capacity(s.len() + 2);
+    for c in s.chars() {
+        match c {
+            '"' => out.push_str("\\\""),
+            '\\' => out.push_str("\\\\"),
+            '\n' => out.push_str("\\n"),
+            '\r' => out.push_str("\\r"),
+            '\t' => out.push_str("\\t"),
+            c if (c as u32) < 0x20 => out.push_str(&format!("\\u{:04x}", c as u32)),
+            c => out.push(c),
+        }
+    }
+    out
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use openidea_plugin::mock::MockHost;
+
+    #[test]
+    fn cases() {
+        let t = |id: &str, s: &str| transform(id).unwrap()(s);
+        assert_eq!(t("camel-case", "hello_world-again"), "helloWorldAgain");
+        assert_eq!(t("pascal-case", "HTTPServer error"), "HttpServerError");
+        assert_eq!(t("snake-case", "parseHTTPResponse2Fast"), "parse_http_response2_fast");
+        assert_eq!(t("screaming-snake-case", "maxValue"), "MAX_VALUE");
+        assert_eq!(t("kebab-case", "  FooBar  "), "  foo-bar  ");
+        assert_eq!(t("dot-case", "a_b"), "a.b");
+        assert_eq!(t("title-case", "the QUICK fox"), "The Quick Fox");
+        assert_eq!(t("toggle-case", "aBc"), "AbC");
+    }
+
+    #[test]
+    fn encodings_round_trip() {
+        for s in ["", "f", "fo", "foo", "héllo wörld ✓"] {
+            assert_eq!(base64_decode(&base64_encode(s.as_bytes())).unwrap(), s.as_bytes());
+            assert_eq!(url_decode(&url_encode(s)), s);
+            assert_eq!(html_unescape(&html_escape(s)), s);
+        }
+        assert_eq!(base64_encode(b"Man"), "TWFu");
+        assert_eq!(url_encode("a b&c"), "a%20b%26c");
+        assert_eq!(html_unescape("&lt;a&gt; &#x41;&#66; &bogus; &"), "<a> AB &bogus; &");
+        assert_eq!(json_escape("a\"b\n"), "a\\\"b\\n");
+    }
+
+    #[test]
+    fn lines_and_numbers() {
+        let t = |id: &str, s: &str| transform(id).unwrap()(s);
+        assert_eq!(t("sort-lines", "b\na\nc"), "a\nb\nc");
+        assert_eq!(t("unique-lines", "a\nb\na"), "a\nb");
+        assert_eq!(t("increment", "v1.09 and -1"), "v2.10 and 0");
+        assert_eq!(t("decrement", "x0"), "x-1");
+    }
+
+    #[test]
+    fn every_selection_and_cursor_in_one_undoable_change() {
+        let host = MockHost::install();
+        host.open_editor("/p/a.rs", "rust", "let fooBar = baz_qux;\n", &[(0, 6, 0, 6), (0, 13, 0, 20)]);
+        StringTools.run_command("snake-case", &host.invocation(), None).unwrap();
+        assert_eq!(host.editor_text(), "let foo_bar = baz_qux;\n");
+        assert_eq!(host.editor_version(), 2, "one change for both");
+        // The editor sends the (moved) selections with the next command.
+        host.open_editor("/p/a.rs", "rust", &host.editor_text(), &[(0, 4, 0, 11), (0, 14, 0, 21)]);
+        StringTools.run_command("upper-case", &host.invocation(), None).unwrap();
+        assert_eq!(host.editor_text(), "let FOO_BAR = BAZ_QUX;\n");
+    }
+
+    #[test]
+    fn line_commands_take_whole_lines() {
+        let host = MockHost::install();
+        host.open_editor("/p/a.txt", "text", "c\nb\na\nz", &[(0, 0, 3, 0)]);
+        StringTools.run_command("sort-lines", &host.invocation(), None).unwrap();
+        assert_eq!(host.editor_text(), "a\nb\nc\nz");
+    }
+
+    #[test]
+    fn degrades_without_write_access() {
+        let host = MockHost::install().with_capabilities(&["editor.read"]);
+        host.open_editor("/p/a.txt", "text", "abc", &[(0, 0, 0, 3)]);
+        let err = StringTools.run_command("upper-case", &host.invocation(), None).unwrap_err();
+        assert!(err.contains("editor.write"), "{err}");
+        assert_eq!(host.editor_text(), "abc");
+    }
+}