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Add a layout solver to google-java-format based on Wadler's prettier printer. - #1482
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…printer. Replace the Oppen-style `Doc.Level` break computation with an immutable document model and a separate solver, based on Philip Wadler's "A prettier printer" (https://homepages.inf.ed.ac.uk/wadler/papers/prettier/prettier.pdf). A `layout.Doc` is built from `text`, `line` and `group`, and `layout.LayoutSolver` lays it out greedily in a single pass: each group is printed flat if it fits (Wadler's `group x = flatten x <|> x`), and otherwise its breaks are taken. Fill breaks correspond to Wadler's `fill`. `layout.LayoutBuilder` bridges the existing visitor to the new model. It provides the same operations as `OpsBuilder`, so `JavaInputAstVisitor` is unchanged apart from the builder type. The builder applies the same rules as the existing engine, for example the group-local fit test and attaching trailing text to the group of the most recent break. All existing formatting is preserved, and every integration test golden is unchanged. PiperOrigin-RevId: 999176908
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Add a layout solver to google-java-format based on Wadler's prettier printer.
Replace the Oppen-style
Doc.Levelbreak computation with an immutabledocument model and a separate solver, based on Philip Wadler's "A prettier
printer" (https://homepages.inf.ed.ac.uk/wadler/papers/prettier/prettier.pdf).
A
layout.Docis built fromtext,lineandgroup, andlayout.LayoutSolverlays it out greedily in a single pass: each group isprinted flat if it fits (Wadler's
group x = flatten x <|> x), and otherwiseits breaks are taken. Fill breaks correspond to Wadler's
fill.layout.LayoutBuilderbridges the existing visitor to the new model. Itprovides the same operations as
OpsBuilder, soJavaInputAstVisitorisunchanged apart from the builder type. The builder applies the same rules as
the existing engine, for example the group-local fit test and attaching
trailing text to the group of the most recent break. All existing formatting
is preserved, and every integration test golden is unchanged.